1 files changed, 126 insertions, 0 deletions
diff --git a/net/llc/llc_station.c b/net/llc/llc_station.c
new file mode 100644
index 000000000..f50654292
--- /dev/null
+++ b/net/llc/llc_station.c
@@ -0,0 +1,126 @@
+/*
+ * llc_station.c - station component of LLC
+ *
+ * Copyright (c) 1997 by Procom Technology, Inc.
+ * 		 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ * This program can be redistributed or modified under the terms of the
+ * GNU General Public License as published by the Free Software Foundation.
+ * This program is distributed without any warranty or implied warranty
+ * of merchantability or fitness for a particular purpose.
+ *
+ * See the GNU General Public License for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <net/llc.h>
+#include <net/llc_sap.h>
+#include <net/llc_conn.h>
+#include <net/llc_c_ac.h>
+#include <net/llc_s_ac.h>
+#include <net/llc_c_ev.h>
+#include <net/llc_c_st.h>
+#include <net/llc_s_ev.h>
+#include <net/llc_s_st.h>
+#include <net/llc_pdu.h>
+
+static int llc_stat_ev_rx_null_dsap_xid_c(struct sk_buff *skb)
+{
+	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
+
+	return LLC_PDU_IS_CMD(pdu) &&			/* command PDU */
+	       LLC_PDU_TYPE_IS_U(pdu) &&		/* U type PDU */
+	       LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_XID &&
+	       !pdu->dsap;				/* NULL DSAP value */
+}
+
+static int llc_stat_ev_rx_null_dsap_test_c(struct sk_buff *skb)
+{
+	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
+
+	return LLC_PDU_IS_CMD(pdu) &&			/* command PDU */
+	       LLC_PDU_TYPE_IS_U(pdu) &&		/* U type PDU */
+	       LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_TEST &&
+	       !pdu->dsap;				/* NULL DSAP */
+}
+
+static int llc_station_ac_send_xid_r(struct sk_buff *skb)
+{
+	u8 mac_da[ETH_ALEN], dsap;
+	int rc = 1;
+	struct sk_buff *nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
+					       sizeof(struct llc_xid_info));
+
+	if (!nskb)
+		goto out;
+	llc_pdu_decode_sa(skb, mac_da);
+	llc_pdu_decode_ssap(skb, &dsap);
+	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
+	llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 127);
+	rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
+	if (unlikely(rc))
+		goto free;
+	dev_queue_xmit(nskb);
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+static int llc_station_ac_send_test_r(struct sk_buff *skb)
+{
+	u8 mac_da[ETH_ALEN], dsap;
+	int rc = 1;
+	u32 data_size;
+	struct sk_buff *nskb;
+
+	if (skb->mac_len < ETH_HLEN)
+		goto out;
+
+	/* The test request command is type U (llc_len = 3) */
+	data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
+	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);
+
+	if (!nskb)
+		goto out;
+	llc_pdu_decode_sa(skb, mac_da);
+	llc_pdu_decode_ssap(skb, &dsap);
+	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
+	llc_pdu_init_as_test_rsp(nskb, skb);
+	rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
+	if (unlikely(rc))
+		goto free;
+	dev_queue_xmit(nskb);
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+/**
+ *	llc_station_rcv - send received pdu to the station state machine
+ *	@skb: received frame.
+ *
+ *	Sends data unit to station state machine.
+ */
+static void llc_station_rcv(struct sk_buff *skb)
+{
+	if (llc_stat_ev_rx_null_dsap_xid_c(skb))
+		llc_station_ac_send_xid_r(skb);
+	else if (llc_stat_ev_rx_null_dsap_test_c(skb))
+		llc_station_ac_send_test_r(skb);
+	kfree_skb(skb);
+}
+
+void __init llc_station_init(void)
+{
+	llc_set_station_handler(llc_station_rcv);
+}
+
+void llc_station_exit(void)
+{
+	llc_set_station_handler(NULL);
+}