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[DCCP]: Move the ack vector code to net/dccp/ackvec.[ch]
authorArnaldo Carvalho de Melo <acme@mandriva.com>
Sun, 18 Sep 2005 07:17:51 +0000 (00:17 -0700)
committerDavid S. Miller <davem@davemloft.net>
Sun, 18 Sep 2005 07:17:51 +0000 (00:17 -0700)
Isolating it, that will be used when we introduce a CCID2 (TCP-Like)
implementation.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/linux/dccp.h
net/dccp/Makefile
net/dccp/ackvec.c [new file with mode: 0644]
net/dccp/ackvec.h [new file with mode: 0644]
net/dccp/dccp.h
net/dccp/input.c
net/dccp/ipv4.c
net/dccp/minisocks.c
net/dccp/options.c
net/dccp/output.c

index 0e72708..8c8e029 100644 (file)
@@ -353,14 +353,8 @@ static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
 
 extern struct inet_timewait_death_row dccp_death_row;
 
-/* Read about the ECN nonce to see why it is 253 */
-#define DCCP_MAX_ACK_VECTOR_LEN 253
-
 struct dccp_options_received {
-       u32     dccpor_ndp:24,
-               dccpor_ack_vector_len:8;
-       u32     dccpor_ack_vector_idx:10;
-       /* 22 bits hole, try to pack */
+       u32     dccpor_ndp; /* only 24 bits */
        u32     dccpor_timestamp;
        u32     dccpor_timestamp_echo;
        u32     dccpor_elapsed_time;
@@ -394,6 +388,8 @@ static inline int dccp_list_has_service(const struct dccp_service_list *sl,
        return 0;
 }
 
+struct dccp_ackvec;
+
 /**
  * struct dccp_sock - DCCP socket state
  *
@@ -414,7 +410,7 @@ static inline int dccp_list_has_service(const struct dccp_service_list *sl,
  * @dccps_packet_size - Set thru setsockopt
  * @dccps_role - Role of this sock, one of %dccp_role
  * @dccps_ndp_count - number of Non Data Packets since last data packet
- * @dccps_hc_rx_ackpkts - receiver half connection acked packets
+ * @dccps_hc_rx_ackvec - rx half connection ack vector
  */
 struct dccp_sock {
        /* inet_connection_sock has to be the first member of dccp_sock */
@@ -439,7 +435,7 @@ struct dccp_sock {
        __u32                           dccps_pmtu_cookie;
        __u32                           dccps_mss_cache;
        struct dccp_options             dccps_options;
-       struct dccp_ackpkts             *dccps_hc_rx_ackpkts;
+       struct dccp_ackvec              *dccps_hc_rx_ackvec;
        void                            *dccps_hc_rx_ccid_private;
        void                            *dccps_hc_tx_ccid_private;
        struct ccid                     *dccps_hc_rx_ccid;
index fb97bb0..344a8da 100644 (file)
@@ -3,6 +3,8 @@ obj-$(CONFIG_IP_DCCP) += dccp.o
 dccp-y := ccid.o input.o ipv4.o minisocks.o options.o output.o proto.o \
          timer.o
 
+dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o
+
 obj-$(CONFIG_INET_DCCP_DIAG) += dccp_diag.o
 
 dccp_diag-y := diag.o
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
new file mode 100644 (file)
index 0000000..6530283
--- /dev/null
@@ -0,0 +1,419 @@
+/*
+ *  net/dccp/ackvec.c
+ *
+ *  An implementation of the DCCP protocol
+ *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
+ *
+ *      This program is free software; you can redistribute it and/or modify it
+ *      under the terms of the GNU General Public License as published by the
+ *      Free Software Foundation; version 2 of the License;
+ */
+
+#include "ackvec.h"
+#include "dccp.h"
+
+#include <linux/dccp.h>
+#include <linux/skbuff.h>
+
+#include <net/sock.h>
+
+int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
+{
+       struct dccp_sock *dp = dccp_sk(sk);
+       struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
+       int len = av->dccpav_vec_len + 2;
+       struct timeval now;
+       u32 elapsed_time;
+       unsigned char *to, *from;
+
+       dccp_timestamp(sk, &now);
+       elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10;
+
+       if (elapsed_time != 0)
+               dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
+
+       if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+               return -1;
+
+       /*
+        * XXX: now we have just one ack vector sent record, so
+        * we have to wait for it to be cleared.
+        *
+        * Of course this is not acceptable, but this is just for
+        * basic testing now.
+        */
+       if (av->dccpav_ack_seqno != DCCP_MAX_SEQNO + 1)
+               return -1;
+
+       DCCP_SKB_CB(skb)->dccpd_opt_len += len;
+
+       to    = skb_push(skb, len);
+       *to++ = DCCPO_ACK_VECTOR_0;
+       *to++ = len;
+
+       len  = av->dccpav_vec_len;
+       from = av->dccpav_buf + av->dccpav_buf_head;
+
+       /* Check if buf_head wraps */
+       if (av->dccpav_buf_head + len > av->dccpav_vec_len) {
+               const u32 tailsize = (av->dccpav_vec_len - av->dccpav_buf_head);
+
+               memcpy(to, from, tailsize);
+               to   += tailsize;
+               len  -= tailsize;
+               from = av->dccpav_buf;
+       }
+
+       memcpy(to, from, len);
+       /*
+        *      From draft-ietf-dccp-spec-11.txt:
+        *
+        *      For each acknowledgement it sends, the HC-Receiver will add an
+        *      acknowledgement record.  ack_seqno will equal the HC-Receiver
+        *      sequence number it used for the ack packet; ack_ptr will equal
+        *      buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
+        *      equal buf_nonce.
+        *
+        * This implemention uses just one ack record for now.
+        */
+       av->dccpav_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+       av->dccpav_ack_ptr   = av->dccpav_buf_head;
+       av->dccpav_ack_ackno = av->dccpav_buf_ackno;
+       av->dccpav_ack_nonce = av->dccpav_buf_nonce;
+       av->dccpav_sent_len  = av->dccpav_vec_len;
+
+       dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
+                     "ack_ackno=%llu\n",
+                     debug_prefix, av->dccpav_sent_len,
+                     (unsigned long long)av->dccpav_ack_seqno,
+                     (unsigned long long)av->dccpav_ack_ackno);
+       return -1;
+}
+
+struct dccp_ackvec *dccp_ackvec_alloc(const unsigned int len,
+                                     const unsigned int __nocast priority)
+{
+       struct dccp_ackvec *av = kmalloc(sizeof(*av) + len, priority);
+
+       if (av != NULL) {
+               av->dccpav_buf_len      = len;
+               av->dccpav_buf_head     =
+                       av->dccpav_buf_tail = av->dccpav_buf_len - 1;
+               av->dccpav_buf_ackno    =
+                       av->dccpav_ack_ackno = av->dccpav_ack_seqno = ~0LLU;
+               av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
+               av->dccpav_ack_ptr      = 0;
+               av->dccpav_time.tv_sec  = 0;
+               av->dccpav_time.tv_usec = 0;
+               av->dccpav_sent_len     = av->dccpav_vec_len = 0;
+       }
+
+       return av;
+}
+
+void dccp_ackvec_free(struct dccp_ackvec *av)
+{
+       kfree(av);
+}
+
+static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
+                                  const unsigned int index)
+{
+       return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK;
+}
+
+static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
+                                const unsigned int index)
+{
+       return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK;
+}
+
+/*
+ * If several packets are missing, the HC-Receiver may prefer to enter multiple
+ * bytes with run length 0, rather than a single byte with a larger run length;
+ * this simplifies table updates if one of the missing packets arrives.
+ */
+static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
+                                                const unsigned int packets,
+                                                 const unsigned char state)
+{
+       unsigned int gap;
+       signed long new_head;
+
+       if (av->dccpav_vec_len + packets > av->dccpav_buf_len)
+               return -ENOBUFS;
+
+       gap      = packets - 1;
+       new_head = av->dccpav_buf_head - packets;
+
+       if (new_head < 0) {
+               if (gap > 0) {
+                       memset(av->dccpav_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
+                              gap + new_head + 1);
+                       gap = -new_head;
+               }
+               new_head += av->dccpav_buf_len;
+       } 
+
+       av->dccpav_buf_head = new_head;
+
+       if (gap > 0)
+               memset(av->dccpav_buf + av->dccpav_buf_head + 1,
+                      DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
+
+       av->dccpav_buf[av->dccpav_buf_head] = state;
+       av->dccpav_vec_len += packets;
+       return 0;
+}
+
+/*
+ * Implements the draft-ietf-dccp-spec-11.txt Appendix A
+ */
+int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
+                   const u64 ackno, const u8 state)
+{
+       /*
+        * Check at the right places if the buffer is full, if it is, tell the
+        * caller to start dropping packets till the HC-Sender acks our ACK
+        * vectors, when we will free up space in dccpav_buf.
+        *
+        * We may well decide to do buffer compression, etc, but for now lets
+        * just drop.
+        *
+        * From Appendix A:
+        *
+        *      Of course, the circular buffer may overflow, either when the
+        *      HC-Sender is sending data at a very high rate, when the
+        *      HC-Receiver's acknowledgements are not reaching the HC-Sender,
+        *      or when the HC-Sender is forgetting to acknowledge those acks
+        *      (so the HC-Receiver is unable to clean up old state). In this
+        *      case, the HC-Receiver should either compress the buffer (by
+        *      increasing run lengths when possible), transfer its state to
+        *      a larger buffer, or, as a last resort, drop all received
+        *      packets, without processing them whatsoever, until its buffer
+        *      shrinks again.
+        */
+
+       /* See if this is the first ackno being inserted */
+       if (av->dccpav_vec_len == 0) {
+               av->dccpav_buf[av->dccpav_buf_head] = state;
+               av->dccpav_vec_len = 1;
+       } else if (after48(ackno, av->dccpav_buf_ackno)) {
+               const u64 delta = dccp_delta_seqno(av->dccpav_buf_ackno,
+                                                  ackno);
+
+               /*
+                * Look if the state of this packet is the same as the
+                * previous ackno and if so if we can bump the head len.
+                */
+               if (delta == 1 &&
+                   dccp_ackvec_state(av, av->dccpav_buf_head) == state &&
+                   (dccp_ackvec_len(av, av->dccpav_buf_head) <
+                    DCCP_ACKVEC_LEN_MASK))
+                       av->dccpav_buf[av->dccpav_buf_head]++;
+               else if (dccp_ackvec_set_buf_head_state(av, delta, state))
+                       return -ENOBUFS;
+       } else {
+               /*
+                * A.1.2.  Old Packets
+                *
+                *      When a packet with Sequence Number S arrives, and
+                *      S <= buf_ackno, the HC-Receiver will scan the table
+                *      for the byte corresponding to S. (Indexing structures
+                *      could reduce the complexity of this scan.)
+                */
+               u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno);
+               unsigned int index = av->dccpav_buf_head;
+
+               while (1) {
+                       const u8 len = dccp_ackvec_len(av, index);
+                       const u8 state = dccp_ackvec_state(av, index);
+                       /*
+                        * valid packets not yet in dccpav_buf have a reserved
+                        * entry, with a len equal to 0.
+                        */
+                       if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
+                           len == 0 && delta == 0) { /* Found our
+                                                        reserved seat! */
+                               dccp_pr_debug("Found %llu reserved seat!\n",
+                                             (unsigned long long)ackno);
+                               av->dccpav_buf[index] = state;
+                               goto out;
+                       }
+                       /* len == 0 means one packet */
+                       if (delta < len + 1)
+                               goto out_duplicate;
+
+                       delta -= len + 1;
+                       if (++index == av->dccpav_buf_len)
+                               index = 0;
+               }
+       }
+
+       av->dccpav_buf_ackno = ackno;
+       dccp_timestamp(sk, &av->dccpav_time);
+out:
+       dccp_pr_debug("");
+       return 0;
+
+out_duplicate:
+       /* Duplicate packet */
+       dccp_pr_debug("Received a dup or already considered lost "
+                     "packet: %llu\n", (unsigned long long)ackno);
+       return -EILSEQ;
+}
+
+#ifdef CONFIG_IP_DCCP_DEBUG
+void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len)
+{
+       if (!dccp_debug)
+               return;
+
+       printk("ACK vector len=%d, ackno=%llu |", len,
+              (unsigned long long)ackno);
+
+       while (len--) {
+               const u8 state = (*vector & DCCP_ACKVEC_STATE_MASK) >> 6;
+               const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
+
+               printk("%d,%d|", state, rl);
+               ++vector;
+       }
+
+       printk("\n");
+}
+
+void dccp_ackvec_print(const struct dccp_ackvec *av)
+{
+       dccp_ackvector_print(av->dccpav_buf_ackno,
+                            av->dccpav_buf + av->dccpav_buf_head,
+                            av->dccpav_vec_len);
+}
+#endif
+
+static void dccp_ackvec_trow_away_ack_record(struct dccp_ackvec *av)
+{
+       /*
+        * As we're keeping track of the ack vector size (dccpav_vec_len) and
+        * the sent ack vector size (dccpav_sent_len) we don't need
+        * dccpav_buf_tail at all, but keep this code here as in the future
+        * we'll implement a vector of ack records, as suggested in
+        * draft-ietf-dccp-spec-11.txt Appendix A. -acme
+        */
+#if 0
+       av->dccpav_buf_tail = av->dccpav_ack_ptr + 1;
+       if (av->dccpav_buf_tail >= av->dccpav_vec_len)
+               av->dccpav_buf_tail -= av->dccpav_vec_len;
+#endif
+       av->dccpav_vec_len -= av->dccpav_sent_len;
+}
+
+void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
+                                const u64 ackno)
+{
+       /* Check if we actually sent an ACK vector */
+       if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
+               return;
+
+       if (ackno == av->dccpav_ack_seqno) {
+#ifdef CONFIG_IP_DCCP_DEBUG
+               struct dccp_sock *dp = dccp_sk(sk);
+               const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
+                                       "CLIENT rx ack: " : "server rx ack: ";
+#endif
+               dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
+                             "ack_ackno=%llu, ACKED!\n",
+                             debug_prefix, 1,
+                             (unsigned long long)av->dccpav_ack_seqno,
+                             (unsigned long long)av->dccpav_ack_ackno);
+               dccp_ackvec_trow_away_ack_record(av);
+               av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
+       }
+}
+
+static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
+                                           struct sock *sk, u64 ackno,
+                                           const unsigned char len,
+                                           const unsigned char *vector)
+{
+       unsigned char i;
+
+       /* Check if we actually sent an ACK vector */
+       if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
+               return;
+       /*
+        * We're in the receiver half connection, so if the received an ACK
+        * vector ackno (e.g. 50) before dccpav_ack_seqno (e.g. 52), we're
+        * not interested.
+        *
+        * Extra explanation with example:
+        * 
+        * if we received an ACK vector with ackno 50, it can only be acking
+        * 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
+        */
+       /* dccp_pr_debug("is %llu < %llu? ", ackno, av->dccpav_ack_seqno); */
+       if (before48(ackno, av->dccpav_ack_seqno)) {
+               /* dccp_pr_debug_cat("yes\n"); */
+               return;
+       }
+       /* dccp_pr_debug_cat("no\n"); */
+
+       i = len;
+       while (i--) {
+               const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
+               u64 ackno_end_rl;
+
+               dccp_set_seqno(&ackno_end_rl, ackno - rl);
+
+               /*
+                * dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
+                * av->dccpav_ack_seqno, ackno);
+                */
+               if (between48(av->dccpav_ack_seqno, ackno_end_rl, ackno)) {
+                       const u8 state = (*vector &
+                                         DCCP_ACKVEC_STATE_MASK) >> 6;
+                       /* dccp_pr_debug_cat("yes\n"); */
+
+                       if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
+#ifdef CONFIG_IP_DCCP_DEBUG
+                               struct dccp_sock *dp = dccp_sk(sk);
+                               const char *debug_prefix =
+                                       dp->dccps_role == DCCP_ROLE_CLIENT ?
+                                       "CLIENT rx ack: " : "server rx ack: ";
+#endif
+                               dccp_pr_debug("%sACK vector 0, len=%d, "
+                                             "ack_seqno=%llu, ack_ackno=%llu, "
+                                             "ACKED!\n",
+                                             debug_prefix, len,
+                                             (unsigned long long)
+                                             av->dccpav_ack_seqno,
+                                             (unsigned long long)
+                                             av->dccpav_ack_ackno);
+                               dccp_ackvec_trow_away_ack_record(av);
+                       }
+                       /*
+                        * If dccpav_ack_seqno was not received, no problem
+                        * we'll send another ACK vector.
+                        */
+                       av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
+                       break;
+               }
+               /* dccp_pr_debug_cat("no\n"); */
+
+               dccp_set_seqno(&ackno, ackno_end_rl - 1);
+               ++vector;
+       }
+}
+
+int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
+                     const u8 opt, const u8 *value, const u8 len)
+{
+       if (len > DCCP_MAX_ACKVEC_LEN)
+               return -1;
+
+       /* dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq, value, len); */
+       dccp_ackvec_check_rcv_ackvector(dccp_sk(sk)->dccps_hc_rx_ackvec, sk,
+                                       DCCP_SKB_CB(skb)->dccpd_ack_seq,
+                                       len, value);
+       return 0;
+}
diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h
new file mode 100644 (file)
index 0000000..8ca51c9
--- /dev/null
@@ -0,0 +1,133 @@
+#ifndef _ACKVEC_H
+#define _ACKVEC_H
+/*
+ *  net/dccp/ackvec.h
+ *
+ *  An implementation of the DCCP protocol
+ *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
+ *
+ *     This program is free software; you can redistribute it and/or modify it
+ *     under the terms of the GNU General Public License version 2 as
+ *     published by the Free Software Foundation.
+ */
+
+#include <linux/config.h>
+#include <linux/compiler.h>
+#include <linux/time.h>
+#include <linux/types.h>
+
+/* Read about the ECN nonce to see why it is 253 */
+#define DCCP_MAX_ACKVEC_LEN 253
+
+#define DCCP_ACKVEC_STATE_RECEIVED     0
+#define DCCP_ACKVEC_STATE_ECN_MARKED   (1 << 6)
+#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6)
+
+#define DCCP_ACKVEC_STATE_MASK         0xC0 /* 11000000 */
+#define DCCP_ACKVEC_LEN_MASK           0x3F /* 00111111 */
+
+/** struct dccp_ackvec - ack vector
+ *
+ * This data structure is the one defined in the DCCP draft
+ * Appendix A.
+ *
+ * @dccpav_buf_head - circular buffer head
+ * @dccpav_buf_tail - circular buffer tail
+ * @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the
+ *                    buffer (i.e. %dccpav_buf_head)
+ * @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
+ *                    by the buffer with State 0
+ *
+ * Additionally, the HC-Receiver must keep some information about the
+ * Ack Vectors it has recently sent. For each packet sent carrying an
+ * Ack Vector, it remembers four variables:
+ *
+ * @dccpav_ack_seqno - the Sequence Number used for the packet
+ *                    (HC-Receiver seqno)
+ * @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement.
+ * @dccpav_ack_ackno - the Acknowledgement Number used for the packet
+ *                    (HC-Sender seqno)
+ * @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
+ *
+ * @dccpav_buf_len     - circular buffer length
+ * @dccpav_time                - the time in usecs
+ * @dccpav_buf - circular buffer of acknowledgeable packets
+ */
+struct dccp_ackvec {
+       unsigned int    dccpav_buf_head;
+       unsigned int    dccpav_buf_tail;
+       u64             dccpav_buf_ackno;
+       u64             dccpav_ack_seqno;
+       u64             dccpav_ack_ackno;
+       unsigned int    dccpav_ack_ptr;
+       unsigned int    dccpav_sent_len;
+       unsigned int    dccpav_vec_len;
+       unsigned int    dccpav_buf_len;
+       struct timeval  dccpav_time;
+       u8              dccpav_buf_nonce;
+       u8              dccpav_ack_nonce;
+       u8              dccpav_buf[0];
+};
+
+struct sock;
+struct sk_buff;
+
+#ifdef CONFIG_IP_DCCP_ACKVEC
+extern struct dccp_ackvec *dccp_ackvec_alloc(unsigned int len,
+                                         const unsigned int __nocast priority);
+extern void dccp_ackvec_free(struct dccp_ackvec *av);
+
+extern int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
+                          const u64 ackno, const u8 state);
+
+extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
+                                       struct sock *sk, const u64 ackno);
+extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
+                            const u8 opt, const u8 *value, const u8 len);
+
+extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
+
+static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
+{
+       return av->dccpav_sent_len != av->dccpav_vec_len;
+}
+#else /* CONFIG_IP_DCCP_ACKVEC */
+static inline struct dccp_ackvec *dccp_ackvec_alloc(unsigned int len,
+                                          const unsigned int __nocast priority)
+{
+       return NULL;
+}
+
+static inline void dccp_ackvec_free(struct dccp_ackvec *av)
+{
+}
+
+static inline int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
+                                 const u64 ackno, const u8 state)
+{
+       return -1;
+}
+
+static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
+                                              struct sock *sk, const u64 ackno)
+{
+}
+
+static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
+                                   const u8 opt, const u8 *value, const u8 len)
+{
+       return -1;
+}
+
+static inline int dccp_insert_option_ackvec(const struct sock *sk,
+                                           const struct sk_buff *skb)
+{
+       return -1;
+}
+
+static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
+{
+       return 0;
+}
+#endif /* CONFIG_IP_DCCP_ACKVEC */
+#endif /* _ACKVEC_H */
index be7a660..5871c02 100644 (file)
@@ -17,6 +17,7 @@
 #include <net/snmp.h>
 #include <net/sock.h>
 #include <net/tcp.h>
+#include "ackvec.h"
 
 #ifdef CONFIG_IP_DCCP_DEBUG
 extern int dccp_debug;
@@ -358,6 +359,17 @@ static inline void dccp_update_gss(struct sock *sk, u64 seq)
                       (dp->dccps_gss -
                        dp->dccps_options.dccpo_sequence_window + 1));
 }
+                               
+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_options.dccpo_send_ack_vector &&
+               dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
+#endif
+              inet_csk_ack_scheduled(sk);
+}
 
 extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
 extern void dccp_insert_option_elapsed_time(struct sock *sk,
@@ -371,65 +383,6 @@ extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
 
 extern struct socket *dccp_ctl_socket;
 
-#define DCCP_ACKPKTS_STATE_RECEIVED    0
-#define DCCP_ACKPKTS_STATE_ECN_MARKED  (1 << 6)
-#define DCCP_ACKPKTS_STATE_NOT_RECEIVED        (3 << 6)
-
-#define DCCP_ACKPKTS_STATE_MASK                0xC0 /* 11000000 */
-#define DCCP_ACKPKTS_LEN_MASK          0x3F /* 00111111 */
-
-/** struct dccp_ackpkts - acknowledgeable packets
- *
- * This data structure is the one defined in the DCCP draft
- * Appendix A.
- *
- * @dccpap_buf_head - circular buffer head
- * @dccpap_buf_tail - circular buffer tail
- * @dccpap_buf_ackno - ack # of the most recent packet acknowledgeable in the
- *                    buffer (i.e. %dccpap_buf_head)
- * @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
- *                    by the buffer with State 0
- *
- * Additionally, the HC-Receiver must keep some information about the
- * Ack Vectors it has recently sent. For each packet sent carrying an
- * Ack Vector, it remembers four variables:
- *
- * @dccpap_ack_seqno - the Sequence Number used for the packet
- *                    (HC-Receiver seqno)
- * @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
- * @dccpap_ack_ackno - the Acknowledgement Number used for the packet
- *                    (HC-Sender seqno)
- * @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
- *
- * @dccpap_buf_len - circular buffer length
- * @dccpap_time                - the time in usecs
- * @dccpap_buf - circular buffer of acknowledgeable packets
- */
-struct dccp_ackpkts {
-       unsigned int            dccpap_buf_head;
-       unsigned int            dccpap_buf_tail;
-       u64                     dccpap_buf_ackno;
-       u64                     dccpap_ack_seqno;
-       u64                     dccpap_ack_ackno;
-       unsigned int            dccpap_ack_ptr;
-       unsigned int            dccpap_buf_vector_len;
-       unsigned int            dccpap_ack_vector_len;
-       unsigned int            dccpap_buf_len;
-       struct timeval          dccpap_time;
-       u8                      dccpap_buf_nonce;
-       u8                      dccpap_ack_nonce;
-       u8                      dccpap_buf[0];
-};
-
-extern struct dccp_ackpkts *
-               dccp_ackpkts_alloc(unsigned int len,
-                                 const unsigned int __nocast priority);
-extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
-extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, const struct sock *sk,
-                           u64 ackno, u8 state);
-extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
-                                        struct sock *sk, u64 ackno);
-
 extern void dccp_timestamp(const struct sock *sk, struct timeval *tv);
 
 static inline suseconds_t timeval_usecs(const struct timeval *tv)
@@ -470,15 +423,4 @@ static inline void timeval_sub_usecs(struct timeval *tv,
        }
 }
 
-#ifdef CONFIG_IP_DCCP_DEBUG
-extern void dccp_ackvector_print(const u64 ackno,
-                                const unsigned char *vector, int len);
-extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
-#else
-static inline void dccp_ackvector_print(const u64 ackno,
-                                       const unsigned char *vector,
-                                       int len) { }
-static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
-#endif
-
 #endif /* _DCCP_H */
index 062e9f8..1b6b2cb 100644 (file)
@@ -16,6 +16,7 @@
 
 #include <net/sock.h>
 
+#include "ackvec.h"
 #include "ccid.h"
 #include "dccp.h"
 
@@ -60,8 +61,8 @@ static inline void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)
        struct dccp_sock *dp = dccp_sk(sk);
 
        if (dp->dccps_options.dccpo_send_ack_vector)
-               dccp_ackpkts_check_rcv_ackno(dp->dccps_hc_rx_ackpkts, sk,
-                                            DCCP_SKB_CB(skb)->dccpd_ack_seq);
+               dccp_ackvec_check_rcv_ackno(dp->dccps_hc_rx_ackvec, sk,
+                                           DCCP_SKB_CB(skb)->dccpd_ack_seq);
 }
 
 static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
@@ -164,37 +165,11 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
        if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
                dccp_event_ack_recv(sk, skb);
 
-       /*
-        * FIXME: check ECN to see if we should use
-        * DCCP_ACKPKTS_STATE_ECN_MARKED
-        */
-       if (dp->dccps_options.dccpo_send_ack_vector) {
-               struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
-
-               if (dccp_ackpkts_add(dp->dccps_hc_rx_ackpkts, sk,
-                                    DCCP_SKB_CB(skb)->dccpd_seq,
-                                    DCCP_ACKPKTS_STATE_RECEIVED)) {
-                       LIMIT_NETDEBUG(KERN_WARNING "DCCP: acknowledgeable "
-                                                   "packets buffer full!\n");
-                       ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
-                       inet_csk_schedule_ack(sk);
-                       inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
-                                                 TCP_DELACK_MIN,
-                                                 DCCP_RTO_MAX);
-                       goto discard;
-               }
-
-               /*
-                * FIXME: this activation is probably wrong, have to study more
-                * TCP delack machinery and how it fits into DCCP draft, but
-                * for now it kinda "works" 8)
-                */
-               if (!inet_csk_ack_scheduled(sk)) {
-                       inet_csk_schedule_ack(sk);
-                       inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 5 * HZ,
-                                                 DCCP_RTO_MAX);
-               }
-       }
+       if (dp->dccps_options.dccpo_send_ack_vector &&
+           dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
+                           DCCP_SKB_CB(skb)->dccpd_seq,
+                           DCCP_ACKVEC_STATE_RECEIVED))
+               goto discard;
 
        ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
        ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
@@ -495,29 +470,11 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
                ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
                ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
 
-               /*
-                * FIXME: check ECN to see if we should use
-                * DCCP_ACKPKTS_STATE_ECN_MARKED
-                */
-               if (dp->dccps_options.dccpo_send_ack_vector) {
-                       if (dccp_ackpkts_add(dp->dccps_hc_rx_ackpkts, sk,
-                                            dcb->dccpd_seq,
-                                            DCCP_ACKPKTS_STATE_RECEIVED))
-                               goto discard;
-                       /*
-                        * FIXME: this activation is probably wrong, have to
-                        * study more TCP delack machinery and how it fits into
-                        * DCCP draft, but for now it kinda "works" 8)
-                        */
-                       if ((dp->dccps_hc_rx_ackpkts->dccpap_ack_seqno ==
-                            DCCP_MAX_SEQNO + 1) &&
-                           !inet_csk_ack_scheduled(sk)) {
-                               inet_csk_schedule_ack(sk);
-                               inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
-                                                         TCP_DELACK_MIN,
-                                                         DCCP_RTO_MAX);
-                       }
-               }
+               if (dp->dccps_options.dccpo_send_ack_vector &&
+                   dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
+                                   DCCP_SKB_CB(skb)->dccpd_seq,
+                                   DCCP_ACKVEC_STATE_RECEIVED))
+                       goto discard;
        }
 
        /*
index 94a440b..82434e4 100644 (file)
@@ -23,6 +23,7 @@
 #include <net/tcp_states.h>
 #include <net/xfrm.h>
 
+#include "ackvec.h"
 #include "ccid.h"
 #include "dccp.h"
 
@@ -1112,45 +1113,7 @@ int dccp_v4_rcv(struct sk_buff *skb)
                goto discard_it;
 
        dh = dccp_hdr(skb);
-#if 0
-       /*
-        * Use something like this to simulate some DATA/DATAACK loss to test
-        * dccp_ackpkts_add, you'll get something like this on a session that
-        * sends 10 DATA/DATAACK packets:
-        *
-        * ackpkts_print: 281473596467422 |0,0|3,0|0,0|3,0|0,0|3,0|0,0|3,0|0,1|
-        *
-        * 0, 0 means: DCCP_ACKPKTS_STATE_RECEIVED, RLE == just this packet
-        * 0, 1 means: DCCP_ACKPKTS_STATE_RECEIVED, RLE == two adjacent packets
-        *                                                 with the same state
-        * 3, 0 means: DCCP_ACKPKTS_STATE_NOT_RECEIVED, RLE == just this packet
-        *
-        * So...
-        *
-        * 281473596467422 was received
-        * 281473596467421 was not received
-        * 281473596467420 was received
-        * 281473596467419 was not received
-        * 281473596467418 was received
-        * 281473596467417 was not received
-        * 281473596467416 was received
-        * 281473596467415 was not received
-        * 281473596467414 was received
-        * 281473596467413 was received (this one was the 3way handshake
-        *                               RESPONSE)
-        *
-        */
-       if (dh->dccph_type == DCCP_PKT_DATA ||
-           dh->dccph_type == DCCP_PKT_DATAACK) {
-               static int discard = 0;
 
-               if (discard) {
-                       discard = 0;
-                       goto discard_it;
-               }
-               discard = 1;
-       }
-#endif
        DCCP_SKB_CB(skb)->dccpd_seq  = dccp_hdr_seq(skb);
        DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
 
@@ -1264,11 +1227,9 @@ static int dccp_v4_init_sock(struct sock *sk)
        do_gettimeofday(&dp->dccps_epoch);
 
        if (dp->dccps_options.dccpo_send_ack_vector) {
-               dp->dccps_hc_rx_ackpkts =
-                       dccp_ackpkts_alloc(DCCP_MAX_ACK_VECTOR_LEN,
-                                          GFP_KERNEL);
-
-               if (dp->dccps_hc_rx_ackpkts == NULL)
+               dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN,
+                                                          GFP_KERNEL);
+               if (dp->dccps_hc_rx_ackvec == NULL)
                        return -ENOMEM;
        }
 
@@ -1288,8 +1249,10 @@ static int dccp_v4_init_sock(struct sock *sk)
                    dp->dccps_hc_tx_ccid == NULL) {
                        ccid_exit(dp->dccps_hc_rx_ccid, sk);
                        ccid_exit(dp->dccps_hc_tx_ccid, sk);
-                       dccp_ackpkts_free(dp->dccps_hc_rx_ackpkts);
-                       dp->dccps_hc_rx_ackpkts = NULL;
+                       if (dp->dccps_options.dccpo_send_ack_vector) {
+                               dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
+                               dp->dccps_hc_rx_ackvec = NULL;
+                       }
                        dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
                        return -ENOMEM;
                }
@@ -1331,8 +1294,10 @@ static int dccp_v4_destroy_sock(struct sock *sk)
 
        ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk);
        ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk);
-       dccp_ackpkts_free(dp->dccps_hc_rx_ackpkts);
-       dp->dccps_hc_rx_ackpkts = NULL;
+       if (dp->dccps_options.dccpo_send_ack_vector) {
+               dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
+               dp->dccps_hc_rx_ackvec = NULL;
+       }
        ccid_exit(dp->dccps_hc_rx_ccid, sk);
        ccid_exit(dp->dccps_hc_tx_ccid, sk);
        dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
index 933e10d..1393461 100644 (file)
@@ -19,6 +19,7 @@
 #include <net/xfrm.h>
 #include <net/inet_timewait_sock.h>
 
+#include "ackvec.h"
 #include "ccid.h"
 #include "dccp.h"
 
@@ -94,23 +95,23 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
                struct dccp_sock *newdp = dccp_sk(newsk);
 
                newdp->dccps_role          = DCCP_ROLE_SERVER;
-               newdp->dccps_hc_rx_ackpkts = NULL;
+               newdp->dccps_hc_rx_ackvec  = NULL;
                newdp->dccps_service_list  = NULL;
                newdp->dccps_service       = dreq->dreq_service;
                newicsk->icsk_rto          = DCCP_TIMEOUT_INIT;
                do_gettimeofday(&newdp->dccps_epoch);
 
                if (newdp->dccps_options.dccpo_send_ack_vector) {
-                       newdp->dccps_hc_rx_ackpkts =
-                               dccp_ackpkts_alloc(DCCP_MAX_ACK_VECTOR_LEN,
-                                                  GFP_ATOMIC);
+                       newdp->dccps_hc_rx_ackvec =
+                               dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN,
+                                                 GFP_ATOMIC);
                        /*
                         * XXX: We're using the same CCIDs set on the parent,
                         * i.e. sk_clone copied the master sock and left the
                         * CCID pointers for this child, that is why we do the
                         * __ccid_get calls.
                         */
-                       if (unlikely(newdp->dccps_hc_rx_ackpkts == NULL))
+                       if (unlikely(newdp->dccps_hc_rx_ackvec == NULL))
                                goto out_free;
                }
 
@@ -118,7 +119,7 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
                                             newsk) != 0 ||
                             ccid_hc_tx_init(newdp->dccps_hc_tx_ccid,
                                             newsk) != 0)) {
-                       dccp_ackpkts_free(newdp->dccps_hc_rx_ackpkts);
+                       dccp_ackvec_free(newdp->dccps_hc_rx_ackvec);
                        ccid_hc_rx_exit(newdp->dccps_hc_rx_ccid, newsk);
                        ccid_hc_tx_exit(newdp->dccps_hc_tx_ccid, newsk);
 out_free:
index d4c4242..c480c50 100644 (file)
 #include <linux/kernel.h>
 #include <linux/skbuff.h>
 
+#include "ackvec.h"
 #include "ccid.h"
 #include "dccp.h"
 
-static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
-                                            struct sock *sk,
-                                            const u64 ackno,
-                                            const unsigned char len,
-                                            const unsigned char *vector);
-
 /* stores the default values for new connection. may be changed with sysctl */
 static const struct dccp_options dccpo_default_values = {
        .dccpo_sequence_window    = DCCPF_INITIAL_SEQUENCE_WINDOW,
@@ -113,25 +108,13 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                                      opt_recv->dccpor_ndp);
                        break;
                case DCCPO_ACK_VECTOR_0:
-                       if (len > DCCP_MAX_ACK_VECTOR_LEN)
-                               goto out_invalid_option;
-
+               case DCCPO_ACK_VECTOR_1:
                        if (pkt_type == DCCP_PKT_DATA)
                                continue;
 
-                       opt_recv->dccpor_ack_vector_len = len;
-                       opt_recv->dccpor_ack_vector_idx = value - options;
-
-                       dccp_pr_debug("%sACK vector 0, len=%d, ack_ackno=%llu\n",
-                                     debug_prefix, len,
-                                     (unsigned long long)
-                                     DCCP_SKB_CB(skb)->dccpd_ack_seq);
-                       dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq,
-                                            value, len);
-                       dccp_ackpkts_check_rcv_ackvector(dp->dccps_hc_rx_ackpkts,
-                                                        sk,
-                                                DCCP_SKB_CB(skb)->dccpd_ack_seq,
-                                                        len, value);
+                       if (dp->dccps_options.dccpo_send_ack_vector &&
+                           dccp_ackvec_parse(sk, skb, opt, value, len))
+                               goto out_invalid_option;
                        break;
                case DCCPO_TIMESTAMP:
                        if (len != 4)
@@ -352,86 +335,6 @@ void dccp_insert_option_elapsed_time(struct sock *sk,
 
 EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
 
-static void dccp_insert_option_ack_vector(struct sock *sk, struct sk_buff *skb)
-{
-       struct dccp_sock *dp = dccp_sk(sk);
-#ifdef CONFIG_IP_DCCP_DEBUG
-       const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
-                                       "CLIENT TX opt: " : "server TX opt: ";
-#endif
-       struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
-       int len = ap->dccpap_buf_vector_len + 2;
-       struct timeval now;
-       u32 elapsed_time;
-       unsigned char *to, *from;
-
-       dccp_timestamp(sk, &now);
-       elapsed_time = timeval_delta(&now, &ap->dccpap_time) / 10;
-
-       if (elapsed_time != 0)
-               dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
-
-       if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
-               LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
-                                        "insert ACK Vector!\n");
-               return;
-       }
-
-       /*
-        * XXX: now we have just one ack vector sent record, so
-        * we have to wait for it to be cleared.
-        *
-        * Of course this is not acceptable, but this is just for
-        * basic testing now.
-        */
-       if (ap->dccpap_ack_seqno != DCCP_MAX_SEQNO + 1)
-               return;
-
-       DCCP_SKB_CB(skb)->dccpd_opt_len += len;
-
-       to    = skb_push(skb, len);
-       *to++ = DCCPO_ACK_VECTOR_0;
-       *to++ = len;
-
-       len  = ap->dccpap_buf_vector_len;
-       from = ap->dccpap_buf + ap->dccpap_buf_head;
-
-       /* Check if buf_head wraps */
-       if (ap->dccpap_buf_head + len > ap->dccpap_buf_len) {
-               const unsigned int tailsize = (ap->dccpap_buf_len -
-                                              ap->dccpap_buf_head);
-
-               memcpy(to, from, tailsize);
-               to   += tailsize;
-               len  -= tailsize;
-               from = ap->dccpap_buf;
-       }
-
-       memcpy(to, from, len);
-       /*
-        *      From draft-ietf-dccp-spec-11.txt:
-        *
-        *      For each acknowledgement it sends, the HC-Receiver will add an
-        *      acknowledgement record.  ack_seqno will equal the HC-Receiver
-        *      sequence number it used for the ack packet; ack_ptr will equal
-        *      buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
-        *      equal buf_nonce.
-        *
-        * This implemention uses just one ack record for now.
-        */
-       ap->dccpap_ack_seqno      = DCCP_SKB_CB(skb)->dccpd_seq;
-       ap->dccpap_ack_ptr        = ap->dccpap_buf_head;
-       ap->dccpap_ack_ackno      = ap->dccpap_buf_ackno;
-       ap->dccpap_ack_nonce      = ap->dccpap_buf_nonce;
-       ap->dccpap_ack_vector_len = ap->dccpap_buf_vector_len;
-
-       dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
-                     "ack_ackno=%llu\n",
-                     debug_prefix, ap->dccpap_ack_vector_len,
-                     (unsigned long long) ap->dccpap_ack_seqno,
-                     (unsigned long long) ap->dccpap_ack_ackno);
-}
-
 void dccp_timestamp(const struct sock *sk, struct timeval *tv)
 {
        const struct dccp_sock *dp = dccp_sk(sk);
@@ -528,9 +431,8 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
 
        if (!dccp_packet_without_ack(skb)) {
                if (dp->dccps_options.dccpo_send_ack_vector &&
-                   (dp->dccps_hc_rx_ackpkts->dccpap_buf_ackno !=
-                    DCCP_MAX_SEQNO + 1))
-                       dccp_insert_option_ack_vector(sk, skb);
+                   dccp_ackvec_pending(dp->dccps_hc_rx_ackvec))
+                       dccp_insert_option_ackvec(sk, skb);
                if (dp->dccps_timestamp_echo != 0)
                        dccp_insert_option_timestamp_echo(sk, skb);
        }
@@ -557,331 +459,3 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
                }
        }
 }
-
-struct dccp_ackpkts *dccp_ackpkts_alloc(const unsigned int len,
-                                       const unsigned int __nocast priority)
-{
-       struct dccp_ackpkts *ap = kmalloc(sizeof(*ap) + len, priority);
-
-       if (ap != NULL) {
-#ifdef CONFIG_IP_DCCP_DEBUG
-               memset(ap->dccpap_buf, 0xFF, len);
-#endif
-               ap->dccpap_buf_len   = len;
-               ap->dccpap_buf_head  =
-                       ap->dccpap_buf_tail =
-                               ap->dccpap_buf_len - 1;
-               ap->dccpap_buf_ackno =
-                       ap->dccpap_ack_ackno =
-                               ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
-               ap->dccpap_buf_nonce = ap->dccpap_buf_nonce = 0;
-               ap->dccpap_ack_ptr   = 0;
-               ap->dccpap_time.tv_sec = 0;
-               ap->dccpap_time.tv_usec = 0;
-               ap->dccpap_buf_vector_len = ap->dccpap_ack_vector_len = 0;
-       }
-
-       return ap;
-}
-
-void dccp_ackpkts_free(struct dccp_ackpkts *ap)
-{
-       if (ap != NULL) {
-#ifdef CONFIG_IP_DCCP_DEBUG
-               memset(ap, 0xFF, sizeof(*ap) + ap->dccpap_buf_len);
-#endif
-               kfree(ap);
-       }
-}
-
-static inline u8 dccp_ackpkts_state(const struct dccp_ackpkts *ap,
-                                   const unsigned int index)
-{
-       return ap->dccpap_buf[index] & DCCP_ACKPKTS_STATE_MASK;
-}
-
-static inline u8 dccp_ackpkts_len(const struct dccp_ackpkts *ap,
-                                 const unsigned int index)
-{
-       return ap->dccpap_buf[index] & DCCP_ACKPKTS_LEN_MASK;
-}
-
-/*
- * If several packets are missing, the HC-Receiver may prefer to enter multiple
- * bytes with run length 0, rather than a single byte with a larger run length;
- * this simplifies table updates if one of the missing packets arrives.
- */
-static inline int dccp_ackpkts_set_buf_head_state(struct dccp_ackpkts *ap,
-                                                 const unsigned int packets,
-                                                 const unsigned char state)
-{
-       unsigned int gap;
-       signed long new_head;
-
-       if (ap->dccpap_buf_vector_len + packets > ap->dccpap_buf_len)
-               return -ENOBUFS;
-
-       gap      = packets - 1;
-       new_head = ap->dccpap_buf_head - packets;
-
-       if (new_head < 0) {
-               if (gap > 0) {
-                       memset(ap->dccpap_buf, DCCP_ACKPKTS_STATE_NOT_RECEIVED,
-                              gap + new_head + 1);
-                       gap = -new_head;
-               }
-               new_head += ap->dccpap_buf_len;
-       } 
-
-       ap->dccpap_buf_head = new_head;
-
-       if (gap > 0)
-               memset(ap->dccpap_buf + ap->dccpap_buf_head + 1,
-                      DCCP_ACKPKTS_STATE_NOT_RECEIVED, gap);
-
-       ap->dccpap_buf[ap->dccpap_buf_head] = state;
-       ap->dccpap_buf_vector_len += packets;
-       return 0;
-}
-
-/*
- * Implements the draft-ietf-dccp-spec-11.txt Appendix A
- */
-int dccp_ackpkts_add(struct dccp_ackpkts *ap, const struct sock *sk,
-                    u64 ackno, u8 state)
-{
-       /*
-        * Check at the right places if the buffer is full, if it is, tell the
-        * caller to start dropping packets till the HC-Sender acks our ACK
-        * vectors, when we will free up space in dccpap_buf.
-        *
-        * We may well decide to do buffer compression, etc, but for now lets
-        * just drop.
-        *
-        * From Appendix A:
-        *
-        *      Of course, the circular buffer may overflow, either when the
-        *      HC-Sender is sending data at a very high rate, when the
-        *      HC-Receiver's acknowledgements are not reaching the HC-Sender,
-        *      or when the HC-Sender is forgetting to acknowledge those acks
-        *      (so the HC-Receiver is unable to clean up old state). In this
-        *      case, the HC-Receiver should either compress the buffer (by
-        *      increasing run lengths when possible), transfer its state to
-        *      a larger buffer, or, as a last resort, drop all received
-        *      packets, without processing them whatsoever, until its buffer
-        *      shrinks again.
-        */
-
-       /* See if this is the first ackno being inserted */
-       if (ap->dccpap_buf_vector_len == 0) {
-               ap->dccpap_buf[ap->dccpap_buf_head] = state;
-               ap->dccpap_buf_vector_len = 1;
-       } else if (after48(ackno, ap->dccpap_buf_ackno)) {
-               const u64 delta = dccp_delta_seqno(ap->dccpap_buf_ackno,
-                                                  ackno);
-
-               /*
-                * Look if the state of this packet is the same as the
-                * previous ackno and if so if we can bump the head len.
-                */
-               if (delta == 1 &&
-                   dccp_ackpkts_state(ap, ap->dccpap_buf_head) == state &&
-                   (dccp_ackpkts_len(ap, ap->dccpap_buf_head) <
-                    DCCP_ACKPKTS_LEN_MASK))
-                       ap->dccpap_buf[ap->dccpap_buf_head]++;
-               else if (dccp_ackpkts_set_buf_head_state(ap, delta, state))
-                       return -ENOBUFS;
-       } else {
-               /*
-                * A.1.2.  Old Packets
-                *
-                *      When a packet with Sequence Number S arrives, and
-                *      S <= buf_ackno, the HC-Receiver will scan the table
-                *      for the byte corresponding to S. (Indexing structures
-                *      could reduce the complexity of this scan.)
-                */
-               u64 delta = dccp_delta_seqno(ackno, ap->dccpap_buf_ackno);
-               unsigned int index = ap->dccpap_buf_head;
-
-               while (1) {
-                       const u8 len = dccp_ackpkts_len(ap, index);
-                       const u8 state = dccp_ackpkts_state(ap, index);
-                       /*
-                        * valid packets not yet in dccpap_buf have a reserved
-                        * entry, with a len equal to 0.
-                        */
-                       if (state == DCCP_ACKPKTS_STATE_NOT_RECEIVED &&
-                           len == 0 && delta == 0) { /* Found our
-                                                        reserved seat! */
-                               dccp_pr_debug("Found %llu reserved seat!\n",
-                                             (unsigned long long) ackno);
-                               ap->dccpap_buf[index] = state;
-                               goto out;
-                       }
-                       /* len == 0 means one packet */
-                       if (delta < len + 1)
-                               goto out_duplicate;
-
-                       delta -= len + 1;
-                       if (++index == ap->dccpap_buf_len)
-                               index = 0;
-               }
-       }
-
-       ap->dccpap_buf_ackno = ackno;
-       dccp_timestamp(sk, &ap->dccpap_time);
-out:
-       dccp_pr_debug("");
-       dccp_ackpkts_print(ap);
-       return 0;
-
-out_duplicate:
-       /* Duplicate packet */
-       dccp_pr_debug("Received a dup or already considered lost "
-                     "packet: %llu\n", (unsigned long long) ackno);
-       return -EILSEQ;
-}
-
-#ifdef CONFIG_IP_DCCP_DEBUG
-void dccp_ackvector_print(const u64 ackno, const unsigned char *vector,
-                         int len)
-{
-       if (!dccp_debug)
-               return;
-
-       printk("ACK vector len=%d, ackno=%llu |", len,
-              (unsigned long long) ackno);
-
-       while (len--) {
-               const u8 state = (*vector & DCCP_ACKPKTS_STATE_MASK) >> 6;
-               const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
-
-               printk("%d,%d|", state, rl);
-               ++vector;
-       }
-
-       printk("\n");
-}
-
-void dccp_ackpkts_print(const struct dccp_ackpkts *ap)
-{
-       dccp_ackvector_print(ap->dccpap_buf_ackno,
-                            ap->dccpap_buf + ap->dccpap_buf_head,
-                            ap->dccpap_buf_vector_len);
-}
-#endif
-
-static void dccp_ackpkts_trow_away_ack_record(struct dccp_ackpkts *ap)
-{
-       /*
-        * As we're keeping track of the ack vector size
-        * (dccpap_buf_vector_len) and the sent ack vector size
-        * (dccpap_ack_vector_len) we don't need dccpap_buf_tail at all, but
-        * keep this code here as in the future we'll implement a vector of
-        * ack records, as suggested in draft-ietf-dccp-spec-11.txt
-        * Appendix A. -acme
-        */
-#if 0
-       ap->dccpap_buf_tail = ap->dccpap_ack_ptr + 1;
-       if (ap->dccpap_buf_tail >= ap->dccpap_buf_len)
-               ap->dccpap_buf_tail -= ap->dccpap_buf_len;
-#endif
-       ap->dccpap_buf_vector_len -= ap->dccpap_ack_vector_len;
-}
-
-void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap, struct sock *sk,
-                                u64 ackno)
-{
-       /* Check if we actually sent an ACK vector */
-       if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
-               return;
-
-       if (ackno == ap->dccpap_ack_seqno) {
-#ifdef CONFIG_IP_DCCP_DEBUG
-               struct dccp_sock *dp = dccp_sk(sk);
-               const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
-                                       "CLIENT rx ack: " : "server rx ack: ";
-#endif
-               dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
-                             "ack_ackno=%llu, ACKED!\n",
-                             debug_prefix, 1,
-                             (unsigned long long) ap->dccpap_ack_seqno,
-                             (unsigned long long) ap->dccpap_ack_ackno);
-               dccp_ackpkts_trow_away_ack_record(ap);
-               ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
-       }
-}
-
-static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
-                                            struct sock *sk, u64 ackno,
-                                            const unsigned char len,
-                                            const unsigned char *vector)
-{
-       unsigned char i;
-
-       /* Check if we actually sent an ACK vector */
-       if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
-               return;
-       /*
-        * We're in the receiver half connection, so if the received an ACK
-        * vector ackno (e.g. 50) before dccpap_ack_seqno (e.g. 52), we're
-        * not interested.
-        *
-        * Extra explanation with example:
-        * 
-        * if we received an ACK vector with ackno 50, it can only be acking
-        * 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
-        */
-       /* dccp_pr_debug("is %llu < %llu? ", ackno, ap->dccpap_ack_seqno); */
-       if (before48(ackno, ap->dccpap_ack_seqno)) {
-               /* dccp_pr_debug_cat("yes\n"); */
-               return;
-       }
-       /* dccp_pr_debug_cat("no\n"); */
-
-       i = len;
-       while (i--) {
-               const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
-               u64 ackno_end_rl;
-
-               dccp_set_seqno(&ackno_end_rl, ackno - rl);
-
-               /*
-                * dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
-                * ap->dccpap_ack_seqno, ackno);
-                */
-               if (between48(ap->dccpap_ack_seqno, ackno_end_rl, ackno)) {
-                       const u8 state = (*vector &
-                                         DCCP_ACKPKTS_STATE_MASK) >> 6;
-                       /* dccp_pr_debug_cat("yes\n"); */
-
-                       if (state != DCCP_ACKPKTS_STATE_NOT_RECEIVED) {
-#ifdef CONFIG_IP_DCCP_DEBUG
-                               struct dccp_sock *dp = dccp_sk(sk);
-                               const char *debug_prefix =
-                                       dp->dccps_role == DCCP_ROLE_CLIENT ?
-                                       "CLIENT rx ack: " : "server rx ack: ";
-#endif
-                               dccp_pr_debug("%sACK vector 0, len=%d, "
-                                             "ack_seqno=%llu, ack_ackno=%llu, "
-                                             "ACKED!\n",
-                                             debug_prefix, len,
-                                             (unsigned long long)
-                                             ap->dccpap_ack_seqno,
-                                             (unsigned long long)
-                                             ap->dccpap_ack_ackno);
-                               dccp_ackpkts_trow_away_ack_record(ap);
-                       }
-                       /*
-                        * If dccpap_ack_seqno was not received, no problem
-                        * we'll send another ACK vector.
-                        */
-                       ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
-                       break;
-               }
-               /* dccp_pr_debug_cat("no\n"); */
-
-               dccp_set_seqno(&ackno, ackno_end_rl - 1);
-               ++vector;
-       }
-}
index 156b1d2..4786bdc 100644 (file)
@@ -16,6 +16,7 @@
 
 #include <net/sock.h>
 
+#include "ackvec.h"
 #include "ccid.h"
 #include "dccp.h"
 
@@ -225,7 +226,6 @@ int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo)
                err = dccp_wait_for_ccid(sk, skb, timeo);
 
        if (err == 0) {
-               const struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
                struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
                const int len = skb->len;
 
@@ -236,15 +236,7 @@ int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo)
                                                  inet_csk(sk)->icsk_rto,
                                                  DCCP_RTO_MAX);
                        dcb->dccpd_type = DCCP_PKT_DATAACK;
-                       /*
-                        * FIXME: we really should have a
-                        * dccps_ack_pending or use icsk.
-                        */
-               } else if (inet_csk_ack_scheduled(sk) ||
-                          dp->dccps_timestamp_echo != 0 ||
-                          (dp->dccps_options.dccpo_send_ack_vector &&
-                           ap->dccpap_buf_ackno != DCCP_MAX_SEQNO + 1 &&
-                           ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1))
+               } else if (dccp_ack_pending(sk))
                        dcb->dccpd_type = DCCP_PKT_DATAACK;
                else
                        dcb->dccpd_type = DCCP_PKT_DATA;