set_ack = 0;
/* fall through */
case DCCP_PKT_DATAACK:
+ case DCCP_PKT_RESET:
break;
case DCCP_PKT_REQUEST:
case DCCP_PKT_SYNC:
case DCCP_PKT_SYNCACK:
- ackno = dcb->dccpd_seq;
+ ackno = dcb->dccpd_ack_seq;
/* fall through */
default:
/*
- * Only data packets should come through with skb->sk
- * set.
+ * Set owner/destructor: some skbs are allocated via
+ * alloc_skb (e.g. when retransmission may happen).
+ * Only Data, DataAck, and Reset packets should come
+ * through here with skb->sk set.
*/
WARN_ON(skb->sk);
skb_set_owner_w(skb, sk);
DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
- memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
err = icsk->icsk_af_ops->queue_xmit(skb, 0);
return net_xmit_eval(err);
}
return -ENOBUFS;
}
+/**
+ * dccp_determine_ccmps - Find out about CCID-specfic packet-size limits
+ * We only consider the HC-sender CCID for setting the CCMPS (RFC 4340, 14.),
+ * since the RX CCID is restricted to feedback packets (Acks), which are small
+ * in comparison with the data traffic. A value of 0 means "no current CCMPS".
+ */
+static u32 dccp_determine_ccmps(const struct dccp_sock *dp)
+{
+ const struct ccid *tx_ccid = dp->dccps_hc_tx_ccid;
+
+ if (tx_ccid == NULL || tx_ccid->ccid_ops == NULL)
+ return 0;
+ return tx_ccid->ccid_ops->ccid_ccmps;
+}
+
unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct dccp_sock *dp = dccp_sk(sk);
- int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len -
- sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext));
+ u32 ccmps = dccp_determine_ccmps(dp);
+ int cur_mps = ccmps ? min(pmtu, ccmps) : pmtu;
- /* Now subtract optional transport overhead */
- mss_now -= icsk->icsk_ext_hdr_len;
+ /* Account for header lengths and IPv4/v6 option overhead */
+ cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len +
+ sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext));
/*
* FIXME: this should come from the CCID infrastructure, where, say,
* make it a multiple of 4
*/
- mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4;
+ cur_mps -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4;
/* And store cached results */
icsk->icsk_pmtu_cookie = pmtu;
- dp->dccps_mss_cache = mss_now;
+ dp->dccps_mss_cache = cur_mps;
- return mss_now;
+ return cur_mps;
}
EXPORT_SYMBOL_GPL(dccp_sync_mss);
wake_up_interruptible(sk->sk_sleep);
/* Should agree with poll, otherwise some programs break */
if (sock_writeable(sk))
- sk_wake_async(sk, 2, POLL_OUT);
+ sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
read_unlock(&sk->sk_callback_lock);
}
/**
* dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet
- * @sk: socket to wait for
+ * @sk: socket to wait for
+ * @skb: current skb to pass on for waiting
+ * @delay: sleep timeout in milliseconds (> 0)
+ * This function is called by default when the socket is closed, and
+ * when a non-zero linger time is set on the socket. For consistency
*/
-static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb)
+static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb, int delay)
{
struct dccp_sock *dp = dccp_sk(sk);
DEFINE_WAIT(wait);
- unsigned long delay;
+ unsigned long jiffdelay;
int rc;
- while (1) {
+ do {
+ dccp_pr_debug("delayed send by %d msec\n", delay);
+ jiffdelay = msecs_to_jiffies(delay);
+
prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+ sk->sk_write_pending++;
+ release_sock(sk);
+ schedule_timeout(jiffdelay);
+ lock_sock(sk);
+ sk->sk_write_pending--;
+
if (sk->sk_err)
goto do_error;
if (signal_pending(current))
goto do_interrupted;
rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
- if (rc <= 0)
- break;
- dccp_pr_debug("delayed send by %d msec\n", rc);
- delay = msecs_to_jiffies(rc);
- sk->sk_write_pending++;
- release_sock(sk);
- schedule_timeout(delay);
- lock_sock(sk);
- sk->sk_write_pending--;
- }
+ } while ((delay = rc) > 0);
out:
finish_wait(sk->sk_sleep, &wait);
return rc;
msecs_to_jiffies(err)+jiffies);
break;
} else
- err = dccp_wait_for_ccid(sk, skb);
+ err = dccp_wait_for_ccid(sk, skb, err);
if (err && err != -EINTR)
DCCP_BUG("err=%d after dccp_wait_for_ccid", err);
}
DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE;
DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss;
- if (dccp_insert_options(sk, skb)) {
+ if (dccp_insert_options_rsk(dreq, skb)) {
kfree_skb(skb);
return NULL;
}
EXPORT_SYMBOL_GPL(dccp_make_response);
-static struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst,
- const enum dccp_reset_codes code)
+/* answer offending packet in @rcv_skb with Reset from control socket @ctl */
+struct sk_buff *dccp_ctl_make_reset(struct socket *ctl, struct sk_buff *rcv_skb)
{
- struct dccp_hdr *dh;
- struct dccp_sock *dp = dccp_sk(sk);
- const u32 dccp_header_size = sizeof(struct dccp_hdr) +
- sizeof(struct dccp_hdr_ext) +
- sizeof(struct dccp_hdr_reset);
- struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1,
- GFP_ATOMIC);
- if (skb == NULL)
- return NULL;
-
- /* Reserve space for headers. */
- skb_reserve(skb, sk->sk_prot->max_header);
-
- skb->dst = dst_clone(dst);
-
- dccp_inc_seqno(&dp->dccps_gss);
-
- DCCP_SKB_CB(skb)->dccpd_reset_code = code;
- DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET;
- DCCP_SKB_CB(skb)->dccpd_seq = dp->dccps_gss;
+ struct dccp_hdr *rxdh = dccp_hdr(rcv_skb), *dh;
+ struct dccp_skb_cb *dcb = DCCP_SKB_CB(rcv_skb);
+ const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
+ sizeof(struct dccp_hdr_ext) +
+ sizeof(struct dccp_hdr_reset);
+ struct dccp_hdr_reset *dhr;
+ struct sk_buff *skb;
- if (dccp_insert_options(sk, skb)) {
- kfree_skb(skb);
+ skb = alloc_skb(ctl->sk->sk_prot->max_header, GFP_ATOMIC);
+ if (skb == NULL)
return NULL;
- }
- dh = dccp_zeroed_hdr(skb, dccp_header_size);
+ skb_reserve(skb, ctl->sk->sk_prot->max_header);
- dh->dccph_sport = inet_sk(sk)->sport;
- dh->dccph_dport = inet_sk(sk)->dport;
- dh->dccph_doff = (dccp_header_size +
- DCCP_SKB_CB(skb)->dccpd_opt_len) / 4;
+ /* Swap the send and the receive. */
+ dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len);
dh->dccph_type = DCCP_PKT_RESET;
+ dh->dccph_sport = rxdh->dccph_dport;
+ dh->dccph_dport = rxdh->dccph_sport;
+ dh->dccph_doff = dccp_hdr_reset_len / 4;
dh->dccph_x = 1;
- dccp_hdr_set_seq(dh, dp->dccps_gss);
- dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dp->dccps_gsr);
- dccp_hdr_reset(skb)->dccph_reset_code = code;
- inet_csk(sk)->icsk_af_ops->send_check(sk, 0, skb);
+ dhr = dccp_hdr_reset(skb);
+ dhr->dccph_reset_code = dcb->dccpd_reset_code;
+
+ switch (dcb->dccpd_reset_code) {
+ case DCCP_RESET_CODE_PACKET_ERROR:
+ dhr->dccph_reset_data[0] = rxdh->dccph_type;
+ break;
+ case DCCP_RESET_CODE_OPTION_ERROR: /* fall through */
+ case DCCP_RESET_CODE_MANDATORY_ERROR:
+ memcpy(dhr->dccph_reset_data, dcb->dccpd_reset_data, 3);
+ break;
+ }
+ /*
+ * From RFC 4340, 8.3.1:
+ * If P.ackno exists, set R.seqno := P.ackno + 1.
+ * Else set R.seqno := 0.
+ */
+ if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
+ dccp_hdr_set_seq(dh, ADD48(dcb->dccpd_ack_seq, 1));
+ dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dcb->dccpd_seq);
- DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
+ dccp_csum_outgoing(skb);
return skb;
}
+EXPORT_SYMBOL_GPL(dccp_ctl_make_reset);
+
+/* send Reset on established socket, to close or abort the connection */
int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code)
{
+ struct sk_buff *skb;
/*
* FIXME: what if rebuild_header fails?
* Should we be doing a rebuild_header here?
*/
- int err = inet_sk_rebuild_header(sk);
-
- if (err == 0) {
- struct sk_buff *skb = dccp_make_reset(sk, sk->sk_dst_cache,
- code);
- if (skb != NULL) {
- memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
- err = inet_csk(sk)->icsk_af_ops->queue_xmit(skb, 0);
- return net_xmit_eval(err);
- }
- }
+ int err = inet_csk(sk)->icsk_af_ops->rebuild_header(sk);
+
+ if (err != 0)
+ return err;
+
+ skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC);
+ if (skb == NULL)
+ return -ENOBUFS;
- return err;
+ /* Reserve space for headers and prepare control bits. */
+ skb_reserve(skb, sk->sk_prot->max_header);
+ DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET;
+ DCCP_SKB_CB(skb)->dccpd_reset_code = code;
+
+ return dccp_transmit_skb(sk, skb);
}
/*
EXPORT_SYMBOL_GPL(dccp_send_ack);
+/* FIXME: Is this still necessary (11.3) - currently nowhere used by DCCP. */
void dccp_send_delayed_ack(struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
}
-void dccp_send_sync(struct sock *sk, const u64 seq,
+void dccp_send_sync(struct sock *sk, const u64 ackno,
const enum dccp_pkt_type pkt_type)
{
/*
*/
struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC);
- if (skb == NULL)
+ if (skb == NULL) {
/* FIXME: how to make sure the sync is sent? */
+ DCCP_CRIT("could not send %s", dccp_packet_name(pkt_type));
return;
+ }
/* Reserve space for headers and prepare control bits. */
skb_reserve(skb, sk->sk_prot->max_header);
DCCP_SKB_CB(skb)->dccpd_type = pkt_type;
- DCCP_SKB_CB(skb)->dccpd_seq = seq;
+ DCCP_SKB_CB(skb)->dccpd_ack_seq = ackno;
dccp_transmit_skb(sk, skb);
}
/* Reserve space for headers and prepare control bits. */
skb_reserve(skb, sk->sk_prot->max_header);
- DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ?
- DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ;
+ if (dp->dccps_role == DCCP_ROLE_SERVER && !dp->dccps_server_timewait)
+ DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSEREQ;
+ else
+ DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE;
if (active) {
dccp_write_xmit(sk, 1);
dccp_skb_entail(sk, skb);
dccp_transmit_skb(sk, skb_clone(skb, prio));
- /* FIXME do we need a retransmit timer here? */
+ /*
+ * Retransmission timer for active-close: RFC 4340, 8.3 requires
+ * to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ
+ * state can be left. The initial timeout is 2 RTTs.
+ * Since RTT measurement is done by the CCIDs, there is no easy
+ * way to get an RTT sample. The fallback RTT from RFC 4340, 3.4
+ * is too low (200ms); we use a high value to avoid unnecessary
+ * retransmissions when the link RTT is > 0.2 seconds.
+ * FIXME: Let main module sample RTTs and use that instead.
+ */
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ DCCP_TIMEOUT_INIT, DCCP_RTO_MAX);
} else
dccp_transmit_skb(sk, skb);
}
projects / linux-2.6-omap-h63xx.git / blobdiff