[DCCP]: Introduce dccp_ipv4_af_ops

And make the core DCCP code AF agnostic, just like TCP, now its time
to work on net/dccp/ipv6.c, we are close to the end!

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

5 files changed, 39 insertions, 14 deletions

diff --git a/net/dccp/input.c b/net/dccp/input.c
index 3454d5941900..c81488fa293e 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -329,7 +329,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
                 dccp_set_state(sk, DCCP_PARTOPEN);
 
                 /* Make sure socket is routed, for correct metrics. */
-                inet_sk_rebuild_header(sk);
+                icsk->icsk_af_ops->rebuild_header(sk);
 
                 if (!sock_flag(sk, SOCK_DEAD)) {
                         sk->sk_state_change(sk);
@@ -444,7 +444,8 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
          */
         if (sk->sk_state == DCCP_LISTEN) {
                 if (dh->dccph_type == DCCP_PKT_REQUEST) {
-                        if (dccp_v4_conn_request(sk, skb) < 0)
+                        if (inet_csk(sk)->icsk_af_ops->conn_request(sk,
+                                                                    skb) < 0)
                                 return 1;
 
                         /* FIXME: do congestion control initialization */
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 1ac3e30ae791..0ce7d0fe5ee7 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -607,6 +607,15 @@ out:
         sock_put(sk);
 }
 
+/* This routine computes an IPv4 DCCP checksum. */
+static void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb)
+{
+        const struct inet_sock *inet = inet_sk(sk);
+        struct dccp_hdr *dh = dccp_hdr(skb);
+
+        dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, inet->daddr);
+}
+
 int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code)
 {
         struct sk_buff *skb;
@@ -1195,6 +1204,19 @@ do_time_wait:
         goto no_dccp_socket;
 }
 
+struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
+        .queue_xmit     = ip_queue_xmit,
+        .send_check     = dccp_v4_send_check,
+        .rebuild_header = inet_sk_rebuild_header,
+        .conn_request   = dccp_v4_conn_request,
+        .syn_recv_sock  = dccp_v4_request_recv_sock,
+        .net_header_len = sizeof(struct iphdr),
+        .setsockopt     = ip_setsockopt,
+        .getsockopt     = ip_getsockopt,
+        .addr2sockaddr  = inet_csk_addr2sockaddr,
+        .sockaddr_len   = sizeof(struct sockaddr_in),
+};
+
 static int dccp_v4_init_sock(struct sock *sk)
 {
         struct dccp_sock *dp = dccp_sk(sk);
@@ -1240,6 +1262,7 @@ static int dccp_v4_init_sock(struct sock *sk)
         inet_csk(sk)->icsk_rto = DCCP_TIMEOUT_INIT;
         sk->sk_state = DCCP_CLOSED;
         sk->sk_write_space = dccp_write_space;
+        inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops;
         dp->dccps_mss_cache = 536;
         dp->dccps_role = DCCP_ROLE_UNDEFINED;
         dp->dccps_service = DCCP_SERVICE_INVALID_VALUE;
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index 1393461898bb..c7ff80cf53a0 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -214,7 +214,7 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
                 goto drop;
         }
 
-        child = dccp_v4_request_recv_sock(sk, skb, req, NULL);
+        child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
         if (child == NULL)
                 goto listen_overflow;
 
diff --git a/net/dccp/output.c b/net/dccp/output.c
index 74ff87025878..f35880503bb8 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -43,6 +43,7 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 {
         if (likely(skb != NULL)) {
                 const struct inet_sock *inet = inet_sk(sk);
+                const struct inet_connection_sock *icsk = inet_csk(sk);
                 struct dccp_sock *dp = dccp_sk(sk);
                 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
                 struct dccp_hdr *dh;
@@ -108,8 +109,7 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
                         break;
                 }
 
-                dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr,
-                                                      inet->daddr);
+                icsk->icsk_af_ops->send_check(sk, skb->len, skb);
 
                 if (set_ack)
                         dccp_event_ack_sent(sk);
@@ -117,7 +117,7 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
                 DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
 
                 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
-                err = ip_queue_xmit(skb, 0);
+                err = icsk->icsk_af_ops->queue_xmit(skb, 0);
                 if (err <= 0)
                         return err;
 
@@ -135,16 +135,14 @@ 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);
-        int mss_now;
-
         /*
          * 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);
          */
-        mss_now = pmtu - sizeof(struct iphdr) - 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));
 
         /* Now subtract optional transport overhead */
         mss_now -= dp->dccps_ext_header_len;
@@ -266,7 +264,7 @@ int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo)
 
 int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
 {
-        if (inet_sk_rebuild_header(sk) != 0)
+        if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk) != 0)
                 return -EHOSTUNREACH; /* Routing failure or similar. */
 
         return dccp_transmit_skb(sk, (skb_cloned(skb) ?
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 8a6b2a9e4581..7b30c12147c2 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -254,7 +254,9 @@ int dccp_setsockopt(struct sock *sk, int level, int optname,
         int val;
 
         if (level != SOL_DCCP)
-                return ip_setsockopt(sk, level, optname, optval, optlen);
+                return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
+                                                             optname, optval,
+                                                             optlen);
 
         if (optlen < sizeof(int))
                 return -EINVAL;
@@ -320,8 +322,9 @@ int dccp_getsockopt(struct sock *sk, int level, int optname,
         int val, len;
 
         if (level != SOL_DCCP)
-                return ip_getsockopt(sk, level, optname, optval, optlen);
-
+                return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
+                                                             optname, optval,
+                                                             optlen);
         if (get_user(len, optlen))
                 return -EFAULT;