-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);
-}
-