Commit d2924569 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

tcp: ipv6: support RFC 6069 (TCP-LD) 



Make tcp_ld_RTO_revert() helper available to IPv6, and
implement RFC 6069 :

Quoting this RFC :

3. Connectivity Disruption Indication

   For Internet Protocol version 6 (IPv6) [RFC2460], the counterpart of
   the ICMP destination unreachable message of code 0 (net unreachable)
   and of code 1 (host unreachable) is the ICMPv6 destination
   unreachable message of code 0 (no route to destination) [RFC4443].
   As with IPv4, a router should generate an ICMPv6 destination
   unreachable message of code 0 in response to a packet that cannot be
   delivered to its destination address because it lacks a matching
   entry in its routing table.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarYuchung Cheng <ycheng@google.com>
Acked-by: default avatarNeal Cardwell <ncardwell@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4d752508

include/net/tcp.h

+1 −0
Original line number Diff line number Diff line
@@ -437,6 +437,7 @@ u16 tcp_get_syncookie_mss(struct request_sock_ops *rsk_ops, 
void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb);

void tcp_v4_mtu_reduced(struct sock *sk);

void tcp_req_err(struct sock *sk, u32 seq, bool abort);

void tcp_ld_RTO_revert(struct sock *sk, u32 seq);

int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb);

struct sock *tcp_create_openreq_child(const struct sock *sk,

				      struct request_sock *req,

net/ipv4/tcp_ipv4.c

+2 −1
Original line number Diff line number Diff line
@@ -404,7 +404,7 @@ void tcp_req_err(struct sock *sk, u32 seq, bool abort) 
EXPORT_SYMBOL(tcp_req_err);



/* TCP-LD (RFC 6069) logic */

static void tcp_ld_RTO_revert(struct sock *sk, u32 seq)

void tcp_ld_RTO_revert(struct sock *sk, u32 seq)

{

	struct inet_connection_sock *icsk = inet_csk(sk);

	struct tcp_sock *tp = tcp_sk(sk);
@@ -441,6 +441,7 @@ static void tcp_ld_RTO_revert(struct sock *sk, u32 seq) 
		tcp_retransmit_timer(sk);

	}

}

EXPORT_SYMBOL(tcp_ld_RTO_revert);



/*

 * This routine is called by the ICMP module when it gets some

net/ipv6/tcp_ipv6.c

+9 −0
Original line number Diff line number Diff line
@@ -473,6 +473,15 @@ static int tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 
		} else

			sk->sk_err_soft = err;

		goto out;

	case TCP_LISTEN:

		break;

	default:

		/* check if this ICMP message allows revert of backoff.

		 * (see RFC 6069)

		 */

		if (!fastopen && type == ICMPV6_DEST_UNREACH &&

		    code == ICMPV6_NOROUTE)

			tcp_ld_RTO_revert(sk, seq);

	}



	if (!sock_owned_by_user(sk) && np->recverr) {

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