diff options
| author | Gerrit Renker <gerrit@erg.abdn.ac.uk> | 2006-11-13 16:12:07 +0100 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-12-03 06:22:17 +0100 |
| commit | e11d9d30802278af22e78d8c10f348b683670cd9 (patch) | |
| tree | ba084b0c5791090164363ad2aaec2c0ab241f603 | |
| parent | [DCCP]: Update comments on precisely which packets can be retransmitted (diff) | |
| download | linux-e11d9d30802278af22e78d8c10f348b683670cd9.tar.xz linux-e11d9d30802278af22e78d8c10f348b683670cd9.zip | |
[DCCP]: Increment sequence numbers on retransmitted Response packets
Problem:
| -rw-r--r-- | net/dccp/minisocks.c | 16 | ||||
| -rw-r--r-- | net/dccp/output.c | 4 |
2 files changed, 13 insertions, 7 deletions
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c index d3de696fe4bf..5b2773efd7c7 100644 --- a/net/dccp/minisocks.c +++ b/net/dccp/minisocks.c @@ -196,15 +196,17 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, /* Check for retransmitted REQUEST */ if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) { - if (after48(DCCP_SKB_CB(skb)->dccpd_seq, - dccp_rsk(req)->dreq_isr)) { - struct dccp_request_sock *dreq = dccp_rsk(req); + struct dccp_request_sock *dreq = dccp_rsk(req); + if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) { dccp_pr_debug("Retransmitted REQUEST\n"); - /* Send another RESPONSE packet */ - dccp_set_seqno(&dreq->dreq_iss, dreq->dreq_iss + 1); - dccp_set_seqno(&dreq->dreq_isr, - DCCP_SKB_CB(skb)->dccpd_seq); + dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq; + /* + * Send another RESPONSE packet + * To protect against Request floods, increment retrans + * counter (backoff, monitored by dccp_response_timer). + */ + req->retrans++; req->rsk_ops->rtx_syn_ack(sk, req, NULL); } /* Network Duplicate, discard packet */ diff --git a/net/dccp/output.c b/net/dccp/output.c index 992caedd7725..08ee5547a2f2 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -332,6 +332,8 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, skb->dst = dst_clone(dst); dreq = dccp_rsk(req); + if (inet_rsk(req)->acked) /* increase ISS upon retransmission */ + dccp_inc_seqno(&dreq->dreq_iss); DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; @@ -354,6 +356,8 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, dccp_csum_outgoing(skb); + /* We use `acked' to remember that a Response was already sent. */ + inet_rsk(req)->acked = 1; DCCP_INC_STATS(DCCP_MIB_OUTSEGS); return skb; } |