[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, 34 insertions, 39 deletions

diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 9f69a67a4b01..3108c9d464f7 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -46,11 +46,13 @@ static void dccp_v4_hash(struct sock *sk)
         inet_hash(&dccp_hashinfo, sk);
 }
 
-static void dccp_v4_unhash(struct sock *sk)
+void dccp_unhash(struct sock *sk)
 {
         inet_unhash(&dccp_hashinfo, sk);
 }
 
+EXPORT_SYMBOL_GPL(dccp_unhash);
+
 /* called with local bh disabled */
 static int __dccp_v4_check_established(struct sock *sk, const __u16 lport,
                                       struct inet_timewait_sock **twp)
@@ -209,8 +211,7 @@ out:
         }
 }
 
-static int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr,
-                           int addr_len)
+int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 {
         struct inet_sock *inet = inet_sk(sk);
         struct dccp_sock *dp = dccp_sk(sk);
@@ -288,16 +289,6 @@ static int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr,
                                                             usin->sin_port);
         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));
-
         inet->id = dp->dccps_iss ^ jiffies;
 
         err = dccp_connect(sk);
@@ -317,6 +308,8 @@ failure:
         goto out;
 }
 
+EXPORT_SYMBOL_GPL(dccp_v4_connect);
+
 /*
  * This routine does path mtu discovery as defined in RFC1191.
  */
@@ -608,7 +601,7 @@ out:
 }
 
 /* This routine computes an IPv4 DCCP checksum. */
-static void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb)
+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);
@@ -616,6 +609,8 @@ static void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb)
         dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, inet->daddr);
 }
 
+EXPORT_SYMBOL_GPL(dccp_v4_send_check);
+
 int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code)
 {
         struct sk_buff *skb;
@@ -651,16 +646,6 @@ static inline u64 dccp_v4_init_sequence(const struct sock *sk,
                                            dccp_hdr(skb)->dccph_sport);
 }
 
-static inline int dccp_bad_service_code(const struct sock *sk,
-                                        const __u32 service)
-{
-        const struct dccp_sock *dp = dccp_sk(sk);
-
-        if (dp->dccps_service == service)
-                return 0;
-        return !dccp_list_has_service(dp->dccps_service_list, service);
-}
-
 int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 {
         struct inet_request_sock *ireq;
@@ -672,7 +657,6 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
         const __u32 service = dccp_hdr_request(skb)->dccph_req_service;
         struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
         __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
-        struct dst_entry *dst = NULL;
 
         /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */
         if (((struct rtable *)skb->dst)->rt_flags &
@@ -713,7 +697,6 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
         ireq = inet_rsk(req);
         ireq->loc_addr = daddr;
         ireq->rmt_addr = saddr;
-        /* FIXME: Merge Aristeu's option parsing code when ready */
         req->rcv_wnd    = 100; /* Fake, option parsing will get the
                                   right value */
         ireq->opt       = NULL;
@@ -731,7 +714,7 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
         dreq->dreq_iss     = dccp_v4_init_sequence(sk, skb);
         dreq->dreq_service = service;
 
-        if (dccp_v4_send_response(sk, req, dst))
+        if (dccp_v4_send_response(sk, req, NULL))
                 goto drop_and_free;
 
         inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
@@ -748,6 +731,8 @@ drop:
         return -1;
 }
 
+EXPORT_SYMBOL_GPL(dccp_v4_conn_request);
+
 /*
  * The three way handshake has completed - we got a valid ACK or DATAACK -
  * now create the new socket.
@@ -802,6 +787,8 @@ exit:
         return NULL;
 }
 
+EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock);
+
 static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
 {
         const struct dccp_hdr *dh = dccp_hdr(skb);
@@ -1021,7 +1008,9 @@ discard:
         return 0;
 }
 
-static inline int dccp_invalid_packet(struct sk_buff *skb)
+EXPORT_SYMBOL_GPL(dccp_v4_do_rcv);
+
+int dccp_invalid_packet(struct sk_buff *skb)
 {
         const struct dccp_hdr *dh;
 
@@ -1075,17 +1064,11 @@ static inline int dccp_invalid_packet(struct sk_buff *skb)
                 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) {
-                LIMIT_NETDEBUG(KERN_WARNING "DCCP: header checksum is "
-                                            "incorrect\n");
-                return 1;
-        }
-
         return 0;
 }
 
+EXPORT_SYMBOL_GPL(dccp_invalid_packet);
+
 /* this is called when real data arrives */
 int dccp_v4_rcv(struct sk_buff *skb)
 {
@@ -1098,6 +1081,14 @@ int dccp_v4_rcv(struct sk_buff *skb)
         if (dccp_invalid_packet(skb))
                 goto discard_it;
 
+        /* 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) {
+                LIMIT_NETDEBUG(KERN_WARNING "%s: incorrect header checksum\n",
+                               __FUNCTION__);
+                goto discard_it;
+        }
+
         dh = dccp_hdr(skb);
 
         DCCP_SKB_CB(skb)->dccpd_seq  = dccp_hdr_seq(skb);
@@ -1217,7 +1208,7 @@ struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
         .sockaddr_len   = sizeof(struct sockaddr_in),
 };
 
-static int dccp_v4_init_sock(struct sock *sk)
+int dccp_v4_init_sock(struct sock *sk)
 {
         struct dccp_sock *dp = dccp_sk(sk);
         static int dccp_ctl_socket_init = 1;
@@ -1270,7 +1261,9 @@ static int dccp_v4_init_sock(struct sock *sk)
         return 0;
 }
 
-static int dccp_v4_destroy_sock(struct sock *sk)
+EXPORT_SYMBOL_GPL(dccp_v4_init_sock);
+
+int dccp_v4_destroy_sock(struct sock *sk)
 {
         struct dccp_sock *dp = dccp_sk(sk);
 
@@ -1303,6 +1296,8 @@ static int dccp_v4_destroy_sock(struct sock *sk)
         return 0;
 }
 
+EXPORT_SYMBOL_GPL(dccp_v4_destroy_sock);
+
 static void dccp_v4_reqsk_destructor(struct request_sock *req)
 {
         kfree(inet_rsk(req)->opt);
@@ -1331,7 +1326,7 @@ struct proto dccp_prot = {
         .recvmsg                = dccp_recvmsg,
         .backlog_rcv            = dccp_v4_do_rcv,
         .hash                   = dccp_v4_hash,
-        .unhash                 = dccp_v4_unhash,
+        .unhash                 = dccp_unhash,
         .accept                 = inet_csk_accept,
         .get_port               = dccp_v4_get_port,
         .shutdown               = dccp_shutdown,