LLC: llc_lookup_listener

With this LLC_CONN_PRIM and friends went to the death row, next
patch will introduce llc_establish_connection, turning on the
electric chair switch for LLC_CONN_PRIM et al.

include/net/llc_conn.h

@@ -99,6 +99,8 @@ extern int llc_conn_remove_acked_pdus(struct sock *conn, u8 nr,
 extern struct sock *llc_lookup_established(struct llc_sap *sap,
 					   struct llc_addr *daddr,
 					   struct llc_addr *laddr);
+extern struct sock *llc_lookup_listener(struct llc_sap *sap,
+					struct llc_addr *laddr);
 extern u8 llc_data_accept_state(u8 state);
 extern void llc_build_offset_table(void);
 #endif /* LLC_CONN_H */

net/llc/llc_c_ac.c

@@ -65,24 +65,14 @@ int llc_conn_ac_conn_ind(struct sock *sk, struct sk_buff *skb)
 	sap = llc_sap_find(dsap);
 	if (sap) {
 		struct llc_conn_state_ev *ev = llc_conn_ev(skb);
-		struct llc_prim_if_block *prim = &sap->llc_ind_prim;
-		union llc_u_prim_data *prim_data = prim->data;
 		struct llc_opt *llc = llc_sk(sk);
 
-		prim_data->conn.daddr.lsap = dsap;
 		llc_pdu_decode_sa(skb, llc->daddr.mac);
 		llc_pdu_decode_da(skb, llc->laddr.mac);
 		llc->dev = skb->dev;
-		prim_data->conn.pri = 0;
-		prim_data->conn.sk  = sk;
-		prim_data->conn.dev = skb->dev;
-		memcpy(&prim_data->conn.daddr, &llc->laddr, sizeof(llc->laddr));
-		memcpy(&prim_data->conn.saddr, &llc->daddr, sizeof(llc->daddr));
-		prim->data   = prim_data;
-		prim->prim   = LLC_CONN_PRIM;
-		prim->sap    = llc->sap;
-		ev->flag     = 1;
-		ev->ind_prim = prim;
+		/* FIXME: find better way to notify upper layer */
+		ev->flag     = LLC_CONN_PRIM + 1;
+		ev->ind_prim = (void *)1;
 		rc = 0;
 	}
 	return rc;

net/llc/llc_conn.c

@@ -18,6 +18,7 @@
 #include <net/llc_sap.h>
 #include <net/llc_conn.h>
 #include <net/sock.h>
+#include <linux/tcp.h>
 #include <net/llc_main.h>
 #include <net/llc_c_ev.h>
 #include <net/llc_c_ac.h>
@@ -61,7 +62,7 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
 	/*
 	 * FIXME: this will vanish as soon I get rid of the double sock crap
 	 */
-	if (flag != LLC_DATA_PRIM + 1)
+	if (flag != LLC_DATA_PRIM + 1 && flag != LLC_CONN_PRIM + 1)
 		llc_conn_free_ev(skb);
 	else if (ind_prim && cfm_prim)
 		skb_get(skb);
@@ -73,7 +74,8 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
 		 * FIXME: this will be saner as soon I get rid of the double
 		 *	  sock crap
 		 */
-		if (flag == LLC_DATA_PRIM + 1) {
+		switch (flag) {
+		case LLC_DATA_PRIM + 1:
 			if (sock_queue_rcv_skb(skb->sk, skb)) {
 				/*
 				 * FIXME: have to sync the LLC state
@@ -86,9 +88,19 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
 				       __FUNCTION__);
 				kfree_skb(skb);
 			}
-		} else
+			break;
+		case LLC_CONN_PRIM + 1: {
+			struct sock *parent = skb->sk;
+
+			skb->sk = sk;
+			skb_queue_tail(&parent->receive_queue, skb);
+			sk->state_change(parent);
+		}
+			break;
+		default:
 			llc->sap->ind(ind_prim);
 		}
+	}
 	if (!cfm_prim)  /* confirmation not required */
 		goto out;
 	/* data confirm has preconditions */
@@ -433,6 +445,39 @@ struct sock *llc_lookup_established(struct llc_sap *sap, struct llc_addr *daddr,
 	return rc;
 }
 
+/**
+ *	llc_lookup_listener - Finds listener for local MAC + SAP
+ *	@sap: SAP
+ *	@laddr: address of local LLC (MAC + SAP)
+ *
+ *	Search connection list of the SAP and finds connection listening on
+ *	local mac, and local sap. Returns pointer for parent socket found,
+ *	%NULL otherwise.
+ */
+struct sock *llc_lookup_listener(struct llc_sap *sap, struct llc_addr *laddr)
+{
+	struct sock *rc = NULL;
+	struct list_head *entry;
+
+	spin_lock_bh(&sap->sk_list.lock);
+	if (list_empty(&sap->sk_list.list))
+		goto out;
+	list_for_each(entry, &sap->sk_list.list) {
+		struct llc_opt *llc = list_entry(entry, struct llc_opt, node);
+
+		if (llc->sk->type != SOCK_STREAM || llc->sk->state != TCP_LISTEN ||
+		    llc->laddr.lsap != laddr->lsap ||
+		    !llc_mac_match(llc->laddr.mac, laddr->mac))
+			continue;
+		rc = llc->sk;
+	}
+	if (rc)
+		sock_hold(rc);
+out:
+	spin_unlock_bh(&sap->sk_list.lock);
+	return rc;
+}
+
 /**
  *	llc_data_accept_state - designates if in this state data can be sent.
  *	@state: state of connection.

net/llc/llc_mac.c

@@ -123,23 +123,33 @@ int llc_rcv(struct sk_buff *skb, struct net_device *dev,
 
 		sk = llc_lookup_established(sap, &saddr, &daddr);
 		if (!sk) {
-			struct llc_opt *llc;
-
-			dprintk("%s: llc_lookup_established failed\n", __FUNCTION__);
 			/*
-			 * FIXME: here we'll pass the sk->family of the
-			 * listening socket, if found, when
-			 * llc_lookup_listener is added in the next patches.
+			 * Didn't find an active connection; verify if there
+			 * is a listening socket for this llc addr
 			 */
-			sk = llc_sk_alloc(PF_LLC, GFP_ATOMIC);
-			if (!sk)
+			struct llc_opt *llc;
+			struct sock *parent;
+			
+			parent = llc_lookup_listener(sap, &daddr);
+
+			if (!parent) {
+				dprintk("llc_lookup_listener failed!\n");
 				goto drop;
+			}
+
+			sk = llc_sk_alloc(parent->family, GFP_ATOMIC);
+			if (!sk) {
+				sock_put(parent);
+				goto drop;
+			}
 			llc = llc_sk(sk);
 			memcpy(&llc->laddr, &daddr, sizeof(llc->laddr));
 			memcpy(&llc->daddr, &saddr, sizeof(llc->daddr));
 			llc_sap_assign_sock(sap, sk);
 			sock_hold(sk);
-		}
+			sock_put(parent);
+			skb->sk = parent;
+		} else
 			skb->sk = sk;
 		bh_lock_sock(sk);
 		if (!sk->lock.users) {

net/llc/llc_sock.c

@@ -923,6 +923,7 @@ static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags)
 	memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
 	memcpy(newllc->addr.sllc_dmac, newllc->daddr.mac, IFHWADDRLEN);
 	newllc->addr.sllc_dsap = newllc->daddr.lsap;
+	newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
 
 	/* put original socket back into a clean listen state. */
 	sk->state = TCP_LISTEN;
@@ -1378,48 +1379,6 @@ static void llc_ui_ind_dataunit(struct llc_prim_if_block *prim)
 out:;
 }
 
-/**
- *	llc_ui_ind_conn - handle CONNECT indication
- *	@prim: Primitive block provided by the llc layer.
- *
- *	handle CONNECT indication.
- */
-static void llc_ui_ind_conn(struct llc_prim_if_block *prim)
-{
-	struct llc_prim_conn *prim_data = &prim->data->conn;
-	struct sock* newsk = prim_data->sk, *parent;
-	struct llc_opt *newllc = llc_sk(newsk);
-	struct sk_buff *skb2;
-
-	parent = llc_ui_find_sk_by_addr(&newllc->laddr, &prim_data->saddr,
-					prim_data->dev);
-	if (!parent) {
-		dprintk("%s: can't find a parent :-(\n", __FUNCTION__);
-		goto out;
-	}
-	dprintk("%s: found parent of remote %02X, its local %02X\n", __FUNCTION__,
-		newllc->daddr.lsap, llc_sk(parent)->laddr.lsap);
-	if (parent->type != SOCK_STREAM || parent->state != TCP_LISTEN) {
-		dprintk("%s: bad parent :-(\n", __FUNCTION__);
-		goto out_put;
-	}
-	if (prim->data->conn.status) {
-		dprintk("%s: bad status :-(\n", __FUNCTION__);
-		goto out_put; /* bad status. */
-	}
-	/* give this connection a link number. */
-	newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
-	skb2 = alloc_skb(0, GFP_ATOMIC);
-	if (!skb2)
-		goto out_put;
-	skb2->sk = newsk;
-	skb_queue_tail(&parent->receive_queue, skb2);
-	parent->state_change(parent);
-out_put:
-	sock_put(parent);
-out:;
-}
-
 /**
  *	llc_ui_ind_disc - handle DISC indication
  *	@prim: Primitive block provided by the llc layer.
@@ -1465,7 +1424,9 @@ static int llc_ui_indicate(struct llc_prim_if_block *prim)
 		case LLC_DATAUNIT_PRIM:
 			llc_ui_ind_dataunit(prim);	break;
 		case LLC_CONN_PRIM:
-			llc_ui_ind_conn(prim);		break;
+			dprintk("%s: shouldn't happen, LLC_CONN_PRIM "
+				"is gone for ->ind()...\n", __FUNCTION__);
+			break;
 		case LLC_DATA_PRIM:
 			dprintk("%s: shouldn't happen, LLC_DATA_PRIM "
 				"is gone for ->ind()...\n", __FUNCTION__);