[SCTP] sctp_connectx() API support

Implements sctp_connectx() as defined in the SCTP sockets API draft by
tunneling the request through a setsockopt().

Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 114 insertions, 37 deletions

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 663843d97a92..7ae6aa772dab 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -191,10 +191,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
         asoc->last_cwr_tsn = asoc->ctsn_ack_point;
         asoc->unack_data = 0;
 
-        SCTP_DEBUG_PRINTK("myctsnap for %s INIT as 0x%x.\n",
-                          asoc->ep->debug_name,
-                          asoc->ctsn_ack_point);
-
         /* ADDIP Section 4.1 Asconf Chunk Procedures
          *
          * When an endpoint has an ASCONF signaled change to be sent to the
@@ -211,6 +207,7 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
 
         /* Make an empty list of remote transport addresses.  */
         INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
+        asoc->peer.transport_count = 0;
 
         /* RFC 2960 5.1 Normal Establishment of an Association
          *
@@ -288,6 +285,7 @@ struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
 
         asoc->base.malloced = 1;
         SCTP_DBG_OBJCNT_INC(assoc);
+        SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc);
 
         return asoc;
 
@@ -356,6 +354,8 @@ void sctp_association_free(struct sctp_association *asoc)
                 sctp_transport_free(transport);
         }
 
+        asoc->peer.transport_count = 0;
+
         /* Free any cached ASCONF_ACK chunk. */
         if (asoc->addip_last_asconf_ack)
                 sctp_chunk_free(asoc->addip_last_asconf_ack);
@@ -400,7 +400,7 @@ void sctp_assoc_set_primary(struct sctp_association *asoc,
         /* If the primary path is changing, assume that the
          * user wants to use this new path.
          */
-        if (transport->active)
+        if (transport->state != SCTP_INACTIVE)
                 asoc->peer.active_path = transport;
 
         /*
@@ -428,10 +428,58 @@ void sctp_assoc_set_primary(struct sctp_association *asoc,
         transport->cacc.next_tsn_at_change = asoc->next_tsn;
 }
 
+/* Remove a transport from an association.  */
+void sctp_assoc_rm_peer(struct sctp_association *asoc,
+                        struct sctp_transport *peer)
+{
+        struct list_head        *pos;
+        struct sctp_transport   *transport;
+
+        SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
+                                 " port: %d\n",
+                                 asoc,
+                                 (&peer->ipaddr),
+                                 peer->ipaddr.v4.sin_port);
+
+        /* If we are to remove the current retran_path, update it
+         * to the next peer before removing this peer from the list.
+         */
+        if (asoc->peer.retran_path == peer)
+                sctp_assoc_update_retran_path(asoc);
+
+        /* Remove this peer from the list. */
+        list_del(&peer->transports);
+
+        /* Get the first transport of asoc. */
+        pos = asoc->peer.transport_addr_list.next;
+        transport = list_entry(pos, struct sctp_transport, transports);
+
+        /* Update any entries that match the peer to be deleted. */
+        if (asoc->peer.primary_path == peer)
+                sctp_assoc_set_primary(asoc, transport);
+        if (asoc->peer.active_path == peer)
+                asoc->peer.active_path = transport;
+        if (asoc->peer.last_data_from == peer)
+                asoc->peer.last_data_from = transport;
+
+        /* If we remove the transport an INIT was last sent to, set it to
+         * NULL. Combined with the update of the retran path above, this
+         * will cause the next INIT to be sent to the next available
+         * transport, maintaining the cycle.
+         */
+        if (asoc->init_last_sent_to == peer)
+                asoc->init_last_sent_to = NULL;
+
+        asoc->peer.transport_count--;
+
+        sctp_transport_free(peer);
+}
+
 /* Add a transport address to an association.  */
 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
                                            const union sctp_addr *addr,
-                                           int gfp)
+                                           const int gfp,
+                                           const int peer_state)
 {
         struct sctp_transport *peer;
         struct sctp_sock *sp;
@@ -442,14 +490,25 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
         /* AF_INET and AF_INET6 share common port field. */
         port = addr->v4.sin_port;
 
+        SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
+                                 " port: %d state:%s\n",
+                                 asoc,
+                                 addr,
+                                 addr->v4.sin_port,
+                                 peer_state == SCTP_UNKNOWN?"UNKNOWN":"ACTIVE");
+
         /* Set the port if it has not been set yet.  */
         if (0 == asoc->peer.port)
                 asoc->peer.port = port;
 
         /* Check to see if this is a duplicate. */
         peer = sctp_assoc_lookup_paddr(asoc, addr);
-        if (peer)
+        if (peer) {
+                if (peer_state == SCTP_ACTIVE &&
+                    peer->state == SCTP_UNKNOWN)
+                     peer->state = SCTP_ACTIVE;
                 return peer;
+        }
 
         peer = sctp_transport_new(addr, gfp);
         if (!peer)
@@ -516,8 +575,12 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
         /* Set the transport's RTO.initial value */
         peer->rto = asoc->rto_initial;
 
+        /* Set the peer's active state. */
+        peer->state = peer_state;
+
         /* Attach the remote transport to our asoc.  */
         list_add_tail(&peer->transports, &asoc->peer.transport_addr_list);
+        asoc->peer.transport_count++;
 
         /* If we do not yet have a primary path, set one.  */
         if (!asoc->peer.primary_path) {
@@ -525,8 +588,9 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
                 asoc->peer.retran_path = peer;
         }
 
-        if (asoc->peer.active_path == asoc->peer.retran_path)
+        if (asoc->peer.active_path == asoc->peer.retran_path) {
                 asoc->peer.retran_path = peer;
+        }
 
         return peer;
 }
@@ -537,37 +601,16 @@ void sctp_assoc_del_peer(struct sctp_association *asoc,
 {
         struct list_head        *pos;
         struct list_head        *temp;
-        struct sctp_transport   *peer = NULL;
         struct sctp_transport   *transport;
 
         list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
                 transport = list_entry(pos, struct sctp_transport, transports);
                 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
-                        peer = transport;
-                        list_del(pos);
+                        /* Do book keeping for removing the peer and free it. */
+                        sctp_assoc_rm_peer(asoc, transport);
                         break;
                 }
         }
-
-        /* The address we want delete is not in the association. */
-        if (!peer)
-                return;
-
-        /* Get the first transport of asoc. */ 
-        pos = asoc->peer.transport_addr_list.next;
-        transport = list_entry(pos, struct sctp_transport, transports);
-
-        /* Update any entries that match the peer to be deleted. */  
-        if (asoc->peer.primary_path == peer)
-                sctp_assoc_set_primary(asoc, transport);
-        if (asoc->peer.active_path == peer)
-                asoc->peer.active_path = transport;
-        if (asoc->peer.retran_path == peer)
-                asoc->peer.retran_path = transport;
-        if (asoc->peer.last_data_from == peer)
-                asoc->peer.last_data_from = transport;
-
-        sctp_transport_free(peer);
 }
 
 /* Lookup a transport by address. */
@@ -608,12 +651,12 @@ void sctp_assoc_control_transport(struct sctp_association *asoc,
         /* Record the transition on the transport.  */
         switch (command) {
         case SCTP_TRANSPORT_UP:
-                transport->active = SCTP_ACTIVE;
+                transport->state = SCTP_ACTIVE;
                 spc_state = SCTP_ADDR_AVAILABLE;
                 break;
 
         case SCTP_TRANSPORT_DOWN:
-                transport->active = SCTP_INACTIVE;
+                transport->state = SCTP_INACTIVE;
                 spc_state = SCTP_ADDR_UNREACHABLE;
                 break;
 
@@ -643,7 +686,7 @@ void sctp_assoc_control_transport(struct sctp_association *asoc,
         list_for_each(pos, &asoc->peer.transport_addr_list) {
                 t = list_entry(pos, struct sctp_transport, transports);
 
-                if (!t->active)
+                if (t->state == SCTP_INACTIVE)
                         continue;
                 if (!first || t->last_time_heard > first->last_time_heard) {
                         second = first;
@@ -663,7 +706,7 @@ void sctp_assoc_control_transport(struct sctp_association *asoc,
          * [If the primary is active but not most recent, bump the most
          * recently used transport.]
          */
-        if (asoc->peer.primary_path->active &&
+        if (asoc->peer.primary_path->state != SCTP_INACTIVE &&
             first != asoc->peer.primary_path) {
                 second = first;
                 first = asoc->peer.primary_path;
@@ -958,7 +1001,7 @@ void sctp_assoc_update(struct sctp_association *asoc,
                                            transports);
                         if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
                                 sctp_assoc_add_peer(asoc, &trans->ipaddr,
-                                                    GFP_ATOMIC);
+                                                    GFP_ATOMIC, SCTP_ACTIVE);
                 }
 
                 asoc->ctsn_ack_point = asoc->next_tsn - 1;
@@ -998,7 +1041,7 @@ void sctp_assoc_update_retran_path(struct sctp_association *asoc)
 
                 /* Try to find an active transport. */
 
-                if (t->active) {
+                if (t->state != SCTP_INACTIVE) {
                         break;
                 } else {
                         /* Keep track of the next transport in case
@@ -1019,6 +1062,40 @@ void sctp_assoc_update_retran_path(struct sctp_association *asoc)
         }
 
         asoc->peer.retran_path = t;
+
+        SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
+                                 " %p addr: ",
+                                 " port: %d\n",
+                                 asoc,
+                                 (&t->ipaddr),
+                                 t->ipaddr.v4.sin_port);
+}
+
+/* Choose the transport for sending a INIT packet.  */
+struct sctp_transport *sctp_assoc_choose_init_transport(
+        struct sctp_association *asoc)
+{
+        struct sctp_transport *t;
+
+        /* Use the retran path. If the last INIT was sent over the
+         * retran path, update the retran path and use it.
+         */
+        if (!asoc->init_last_sent_to) {
+                t = asoc->peer.active_path;
+        } else {
+                if (asoc->init_last_sent_to == asoc->peer.retran_path)
+                        sctp_assoc_update_retran_path(asoc);
+                t = asoc->peer.retran_path;
+        }
+
+        SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
+                                 " %p addr: ",
+                                 " port: %d\n",
+                                 asoc,
+                                 (&t->ipaddr),
+                                 t->ipaddr.v4.sin_port);
+
+        return t;
 }
 
 /* Choose the transport for sending a SHUTDOWN packet.  */