[DCCP]: Send SYNCACK packets in response to SYNC packets
Also fix step 6 when receiving SYNC or SYNCACK packets, i.e. we were not using
the updated swl.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h
index fff794c..4efdce4 100644
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -122,7 +122,8 @@
extern int dccp_send_response(struct sock *sk);
extern void dccp_send_ack(struct sock *sk);
extern void dccp_send_delayed_ack(struct sock *sk);
-extern void dccp_send_sync(struct sock *sk, u64 seq);
+extern void dccp_send_sync(struct sock *sk, const u64 seq,
+ const enum dccp_pkt_type pkt_type);
extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb,
const int len);
diff --git a/net/dccp/input.c b/net/dccp/input.c
index 9dadfc3..68b6e72 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -50,7 +50,7 @@
* Drop packet and return
*/
if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) {
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
return;
}
@@ -76,8 +76,7 @@
{
const struct dccp_hdr *dh = dccp_hdr(skb);
struct dccp_sock *dp = dccp_sk(sk);
- u64 lswl = dp->dccps_swl;
- u64 lawl = dp->dccps_awl;
+ u64 lswl, lawl;
/*
* Step 5: Prepare sequence numbers for Sync
@@ -99,6 +98,8 @@
dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq);
else
return -1;
+ }
+
/*
* Step 6: Check sequence numbers
* Let LSWL = S.SWL and LAWL = S.AWL
@@ -113,7 +114,10 @@
* Send Sync packet acknowledging P.seqno
* Drop packet and return
*/
- } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ ||
+ lswl = dp->dccps_swl;
+ lawl = dp->dccps_awl;
+
+ if (dh->dccph_type == DCCP_PKT_CLOSEREQ ||
dh->dccph_type == DCCP_PKT_CLOSE ||
dh->dccph_type == DCCP_PKT_RESET) {
lswl = dp->dccps_gsr;
@@ -132,8 +136,8 @@
DCCP_PKT_WITHOUT_ACK_SEQ))
dp->dccps_gar = DCCP_SKB_CB(skb)->dccpd_ack_seq;
} else {
- dccp_pr_debug("Step 6 failed, sending SYNC...\n");
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ LIMIT_NETDEBUG("Step 6 failed, sending SYNC...\n");
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
return -1;
}
@@ -242,9 +246,21 @@
check_seq:
if (!before48(DCCP_SKB_CB(skb)->dccpd_seq, dp->dccps_osr)) {
send_sync:
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_PKT_SYNC);
}
break;
+ case DCCP_PKT_SYNC:
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_PKT_SYNCACK);
+ /*
+ * From the draft:
+ *
+ * As with DCCP-Ack packets, DCCP-Sync and DCCP-SyncAck packets
+ * MAY have non-zero-length application data areas, whose
+ * contents * receivers MUST ignore.
+ */
+ goto discard;
}
DCCP_INC_STATS_BH(DCCP_MIB_INERRS);
@@ -517,7 +533,8 @@
dh->dccph_type == DCCP_PKT_REQUEST) ||
(sk->sk_state == DCCP_RESPOND &&
dh->dccph_type == DCCP_PKT_DATA)) {
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_PKT_SYNC);
goto discard;
}
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index bc3cfc0..335e00e 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -376,7 +376,7 @@
* probing, since DCCP-Sync probes do not risk application
* data loss.
*/
- dccp_send_sync(sk, dp->dccps_gsr);
+ dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC);
} /* else let the usual retransmit timer handle it */
}
@@ -1008,7 +1008,7 @@
return 1;
if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) {
- dccp_pr_debug("pskb_may_pull failed\n");
+ printk(KERN_WARNING "DCCP: pskb_may_pull failed\n");
return 1;
}
@@ -1016,7 +1016,7 @@
/* If the packet type is not understood, drop packet and return */
if (dh->dccph_type >= DCCP_PKT_INVALID) {
- dccp_pr_debug("invalid packet type\n");
+ printk(KERN_WARNING "DCCP: invalid packet type\n");
return 1;
}
@@ -1025,12 +1025,13 @@
* packet, drop packet and return
*/
if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) {
- dccp_pr_debug("Offset(%u) too small 1\n", dh->dccph_doff);
+ printk(KERN_WARNING "DCCP: Offset(%u) too small 1\n",
+ dh->dccph_doff);
return 1;
}
if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) {
- dccp_pr_debug("P.Data Offset(%u) too small 2\n",
+ printk(KERN_WARNING "DCCP: P.Data Offset(%u) too small 2\n",
dh->dccph_doff);
return 1;
}
@@ -1045,15 +1046,16 @@
dh->dccph_type != DCCP_PKT_DATA &&
dh->dccph_type != DCCP_PKT_ACK &&
dh->dccph_type != DCCP_PKT_DATAACK) {
- dccp_pr_debug("P.type (%s) not Data, Ack nor DataAck and "
- "P.X == 0\n", dccp_packet_name(dh->dccph_type));
+ printk(KERN_WARNING "DCCP: P.type (%s) not Data, Ack nor "
+ "DataAck and P.X == 0\n",
+ dccp_packet_name(dh->dccph_type));
return 1;
}
/* If the header checksum is incorrect, drop packet and return */
if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr,
skb->nh.iph->daddr) < 0) {
- dccp_pr_debug("header checksum is incorrect\n");
+ printk(KERN_WARNING "DCCP: header checksum is incorrect\n");
return 1;
}
diff --git a/net/dccp/output.c b/net/dccp/output.c
index dcc061b..384fd09 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -404,7 +404,8 @@
sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
}
-void dccp_send_sync(struct sock *sk, u64 seq)
+void dccp_send_sync(struct sock *sk, const u64 seq,
+ const enum dccp_pkt_type pkt_type)
{
/*
* We are not putting this on the write queue, so
@@ -420,7 +421,7 @@
/* Reserve space for headers and prepare control bits. */
skb_reserve(skb, MAX_DCCP_HEADER);
skb->csum = 0;
- DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_SYNC;
+ DCCP_SKB_CB(skb)->dccpd_type = pkt_type;
DCCP_SKB_CB(skb)->dccpd_seq = seq;
skb_set_owner_w(skb, sk);