[DCCP]: Prepare the AF agnostic core for the introduction of DCCPv6

Basically exports a similar set of functions as the one exported by
the non-AF specific TCP code.

In the process moved some non-AF specific code from dccp_v4_connect to
dccp_connect_init and moved the checksum verification from
dccp_invalid_packet to dccp_v4_rcv, so as to use it in dccp_v6_rcv
too.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 10 deletions

diff --git a/net/dccp/output.c b/net/dccp/output.c
index f35880503bb8..c40f7f8a328b 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -135,12 +135,6 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
 {
         struct dccp_sock *dp = dccp_sk(sk);
-        /*
-         * FIXME: we really should be using the af_specific thing to support
-         *        IPv6.
-         * mss_now = pmtu - tp->af_specific->net_header_len -
-         *           sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext);
-         */
         int mss_now = (pmtu - inet_csk(sk)->icsk_af_ops->net_header_len -
                        sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext));
 
@@ -164,6 +158,8 @@ unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
         return mss_now;
 }
 
+EXPORT_SYMBOL_GPL(dccp_sync_mss);
+
 void dccp_write_space(struct sock *sk)
 {
         read_lock(&sk->sk_callback_lock);
@@ -319,6 +315,8 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst,
         return skb;
 }
 
+EXPORT_SYMBOL_GPL(dccp_make_response);
+
 struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst,
                                 const enum dccp_reset_codes code)
                                    
@@ -375,6 +373,7 @@ struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst,
  */
 static inline void dccp_connect_init(struct sock *sk)
 {
+        struct dccp_sock *dp = dccp_sk(sk);
         struct dst_entry *dst = __sk_dst_get(sk);
         struct inet_connection_sock *icsk = inet_csk(sk);
 
@@ -383,10 +382,16 @@ static inline void dccp_connect_init(struct sock *sk)
         
         dccp_sync_mss(sk, dst_mtu(dst));
 
-        /*
-         * FIXME: set dp->{dccps_swh,dccps_swl}, with
-         * something like dccp_inc_seq
-         */
+        dccp_update_gss(sk, dp->dccps_iss);
+        /*
+         * SWL and AWL are initially adjusted so that they are not less than
+         * the initial Sequence Numbers received and sent, respectively:
+         *      SWL := max(GSR + 1 - floor(W/4), ISR),
+         *      AWL := max(GSS - W' + 1, ISS).
+         * These adjustments MUST be applied only at the beginning of the
+         * connection.
+         */
+        dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));
 
         icsk->icsk_retransmits = 0;
 }
@@ -418,6 +423,8 @@ int dccp_connect(struct sock *sk)
         return 0;
 }
 
+EXPORT_SYMBOL_GPL(dccp_connect);
+
 void dccp_send_ack(struct sock *sk)
 {
         /* If we have been reset, we may not send again. */