patch-2.0.35 linux/net/rose/rose_in.c

• Lines: 344
• Date: Mon Jul 13 13:47:41 1998
• Orig file: v2.0.34/linux/net/rose/rose_in.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.0.34/linux/net/rose/rose_in.c linux/net/rose/rose_in.c
@@ -0,0 +1,343 @@
+/*
+ *	ROSE release 003
+ *
+ *	This code REQUIRES 2.1.0 or higher/ NET3.029
+ *
+ *	This module:
+ *		This module is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ *	Most of this code is based on the SDL diagrams published in the 7th
+ *	ARRL Computer Networking Conference papers. The diagrams have mistakes
+ *	in them, but are mostly correct. Before you modify the code could you
+ *	read the SDL diagrams as the code is not obvious and probably very
+ *	easy to break;
+ *
+ *	History
+ *	ROSE 001	Jonathan(G4KLX)	Cloned from nr_in.c
+ *	ROSE 003	Jonathan(G4KLX)	Removed M bit processing.
+ */
+
+#include <linux/config.h>
+#if defined(CONFIG_ROSE) || defined(CONFIG_ROSE_MODULE)
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/ip.h>			/* For ip_rcv */
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/rose.h>
+
+/*
+ * State machine for state 1, Awaiting Call Accepted State.
+ * The handling of the timer(s) is in file rose_timer.c.
+ * Handling of state 0 and connection release is in af_rose.c.
+ */
+static int rose_state1_machine(struct sock *sk, struct sk_buff *skb, int frametype)
+{
+	switch (frametype) {
+
+		case ROSE_CALL_ACCEPTED:
+			sk->protinfo.rose->condition = 0x00;
+			sk->protinfo.rose->timer     = 0;
+			sk->protinfo.rose->vs        = 0;
+			sk->protinfo.rose->va        = 0;
+			sk->protinfo.rose->vr        = 0;
+			sk->protinfo.rose->vl        = 0;
+			sk->protinfo.rose->state     = ROSE_STATE_3;
+			sk->state                    = TCP_ESTABLISHED;
+			if (!sk->dead)
+				sk->state_change(sk);
+			break;
+
+		case ROSE_CLEAR_REQUEST:
+			rose_clear_queues(sk);
+			rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION);
+			sk->protinfo.rose->neighbour->use--;
+			sk->protinfo.rose->cause      = skb->data[3];
+			sk->protinfo.rose->diagnostic = skb->data[4];
+			sk->protinfo.rose->state = ROSE_STATE_0;
+			sk->state                = TCP_CLOSE;
+			sk->err                  = ECONNREFUSED;
+			sk->shutdown            |= SEND_SHUTDOWN;
+			if (!sk->dead)
+				sk->state_change(sk);
+			sk->dead                 = 1;
+			break;
+
+		default:
+			break;
+	}
+
+	return 0;
+}
+
+/*
+ * State machine for state 2, Awaiting Clear Confirmation State.
+ * The handling of the timer(s) is in file rose_timer.c
+ * Handling of state 0 and connection release is in af_rose.c.
+ */
+static int rose_state2_machine(struct sock *sk, struct sk_buff *skb, int frametype)
+{
+	switch (frametype) {
+
+		case ROSE_CLEAR_REQUEST:
+			rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION);
+			sk->protinfo.rose->cause      = skb->data[3];
+			sk->protinfo.rose->diagnostic = skb->data[4];
+		case ROSE_CLEAR_CONFIRMATION:
+			rose_clear_queues(sk);
+			sk->protinfo.rose->neighbour->use--;
+			sk->protinfo.rose->state = ROSE_STATE_0;
+			sk->state                = TCP_CLOSE;
+			sk->err                  = 0;
+			sk->shutdown            |= SEND_SHUTDOWN;
+			if (!sk->dead)
+				sk->state_change(sk);
+			sk->dead                 = 1;
+			break;
+
+		default:
+			break;
+	}
+
+	return 0;
+}
+
+/*
+ * State machine for state 3, Connected State.
+ * The handling of the timer(s) is in file rose_timer.c
+ * Handling of state 0 and connection release is in af_rose.c.
+ */
+static int rose_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype, int ns, int nr, int q, int d, int m)
+{
+	int queued = 0;
+
+	switch (frametype) {
+
+		case ROSE_RESET_REQUEST:
+			rose_write_internal(sk, ROSE_RESET_CONFIRMATION);
+			sk->protinfo.rose->condition = 0x00;
+			sk->protinfo.rose->timer     = 0;
+			sk->protinfo.rose->vs        = 0;
+			sk->protinfo.rose->vr        = 0;
+			sk->protinfo.rose->va        = 0;
+			sk->protinfo.rose->vl        = 0;
+			break;
+
+		case ROSE_CLEAR_REQUEST:
+			rose_clear_queues(sk);
+			rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION);
+			sk->protinfo.rose->neighbour->use--;
+			sk->protinfo.rose->cause      = skb->data[3];
+			sk->protinfo.rose->diagnostic = skb->data[4];
+			sk->protinfo.rose->state = ROSE_STATE_0;
+			sk->state                = TCP_CLOSE;
+			sk->err                  = 0;
+			sk->shutdown            |= SEND_SHUTDOWN;
+			if (!sk->dead)
+				sk->state_change(sk);
+			sk->dead                 = 1;
+			break;
+
+		case ROSE_RR:
+		case ROSE_RNR:
+			if (frametype == ROSE_RNR)
+				sk->protinfo.rose->condition |= ROSE_COND_PEER_RX_BUSY;
+			else
+				sk->protinfo.rose->condition &= ~ROSE_COND_PEER_RX_BUSY;
+			if (!rose_validate_nr(sk, nr)) {
+				rose_clear_queues(sk);
+				rose_write_internal(sk, ROSE_RESET_REQUEST);
+				sk->protinfo.rose->condition = 0x00;
+				sk->protinfo.rose->vs        = 0;
+				sk->protinfo.rose->vr        = 0;
+				sk->protinfo.rose->va        = 0;
+				sk->protinfo.rose->vl        = 0;
+				sk->protinfo.rose->state     = ROSE_STATE_4;
+				sk->protinfo.rose->timer     = sk->protinfo.rose->t2;
+			} else {
+				if (sk->protinfo.rose->condition & ROSE_COND_PEER_RX_BUSY) {
+					sk->protinfo.rose->va = nr;
+				} else {
+					rose_check_iframes_acked(sk, nr);
+				}
+			}
+			break;
+
+		case ROSE_DATA:	/* XXX */
+			sk->protinfo.rose->condition &= ~ROSE_COND_PEER_RX_BUSY;
+			if (!rose_validate_nr(sk, nr)) {
+				rose_clear_queues(sk);
+				rose_write_internal(sk, ROSE_RESET_REQUEST);
+				sk->protinfo.rose->condition = 0x00;
+				sk->protinfo.rose->vs        = 0;
+				sk->protinfo.rose->vr        = 0;
+				sk->protinfo.rose->va        = 0;
+				sk->protinfo.rose->vl        = 0;
+				sk->protinfo.rose->state     = ROSE_STATE_4;
+				sk->protinfo.rose->timer     = sk->protinfo.rose->t2;
+				break;
+			}
+			if (sk->protinfo.rose->condition & ROSE_COND_PEER_RX_BUSY) {
+				sk->protinfo.rose->va = nr;
+			} else {
+				rose_check_iframes_acked(sk, nr);
+			}
+			if (sk->protinfo.rose->condition & ROSE_COND_OWN_RX_BUSY)
+				break;
+			if (ns == sk->protinfo.rose->vr) {
+				if (sock_queue_rcv_skb(sk, skb) == 0) {
+					sk->protinfo.rose->vr = (sk->protinfo.rose->vr + 1) % ROSE_MODULUS;
+					queued = 1;
+				} else {
+					sk->protinfo.rose->condition |= ROSE_COND_OWN_RX_BUSY;
+				}
+			}
+			/*
+			 * If the window is full, ack the frame, else start the
+			 * acknowledge hold back timer.
+			 */
+			if (((sk->protinfo.rose->vl + sysctl_rose_window_size) % ROSE_MODULUS) == sk->protinfo.rose->vr) {
+				sk->protinfo.rose->condition &= ~ROSE_COND_ACK_PENDING;
+				sk->protinfo.rose->timer      = 0;
+				rose_enquiry_response(sk);
+			} else {
+				sk->protinfo.rose->condition |= ROSE_COND_ACK_PENDING;
+				sk->protinfo.rose->timer      = sk->protinfo.rose->hb;
+			}
+			break;
+
+		default:
+			printk(KERN_WARNING "rose: unknown %02X in state 3\n", frametype);
+			break;
+	}
+
+	return queued;
+}
+
+/*
+ * State machine for state 4, Awaiting Reset Confirmation State.
+ * The handling of the timer(s) is in file rose_timer.c
+ * Handling of state 0 and connection release is in af_rose.c.
+ */
+static int rose_state4_machine(struct sock *sk, struct sk_buff *skb, int frametype)
+{
+	switch (frametype) {
+
+		case ROSE_RESET_REQUEST:
+			rose_write_internal(sk, ROSE_RESET_CONFIRMATION);
+		case ROSE_RESET_CONFIRMATION:
+			sk->protinfo.rose->timer     = 0;
+			sk->protinfo.rose->condition = 0x00;
+			sk->protinfo.rose->va        = 0;
+			sk->protinfo.rose->vr        = 0;
+			sk->protinfo.rose->vs        = 0;
+			sk->protinfo.rose->vl        = 0;
+			sk->protinfo.rose->state     = ROSE_STATE_3;
+			break;
+
+		case ROSE_CLEAR_REQUEST:
+			rose_clear_queues(sk);
+			rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION);
+			sk->protinfo.rose->neighbour->use--;
+			sk->protinfo.rose->cause      = skb->data[3];
+			sk->protinfo.rose->diagnostic = skb->data[4];
+			sk->protinfo.rose->timer = 0;
+			sk->protinfo.rose->state = ROSE_STATE_0;
+			sk->state                = TCP_CLOSE;
+			sk->err                  = 0;
+			sk->shutdown            |= SEND_SHUTDOWN;
+			if (!sk->dead)
+				sk->state_change(sk);
+			sk->dead                 = 1;
+			break;
+
+		default:
+			break;
+	}
+
+	return 0;
+}
+
+/*
+ * State machine for state 5, Awaiting Call Acceptance State.
+ * The handling of the timer(s) is in file rose_timer.c
+ * Handling of state 0 and connection release is in af_rose.c.
+ */
+static int rose_state5_machine(struct sock *sk, struct sk_buff *skb, int frametype)
+{
+	switch (frametype) {
+
+		case ROSE_CLEAR_REQUEST:
+			rose_clear_queues(sk);
+			rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION);
+			sk->protinfo.rose->neighbour->use--;
+			sk->protinfo.rose->cause      = skb->data[3];
+			sk->protinfo.rose->diagnostic = skb->data[4];
+			sk->protinfo.rose->state = ROSE_STATE_0;
+			sk->state                = TCP_CLOSE;
+			sk->err                  = 0;
+			sk->shutdown            |= SEND_SHUTDOWN;
+			if (!sk->dead)
+				sk->state_change(sk);
+			sk->dead                 = 1;
+			break;
+	}
+
+	return 0;
+}
+
+/* Higher level upcall for a LAPB frame */
+int rose_process_rx_frame(struct sock *sk, struct sk_buff *skb)
+{
+	int queued = 0, frametype, ns, nr, q, d, m;
+
+	if (sk->protinfo.rose->state == ROSE_STATE_0)
+		return 0;
+
+	del_timer(&sk->timer);
+
+	frametype = rose_decode(skb, &ns, &nr, &q, &d, &m);
+
+	switch (sk->protinfo.rose->state) {
+		case ROSE_STATE_1:
+			queued = rose_state1_machine(sk, skb, frametype);
+			break;
+		case ROSE_STATE_2:
+			queued = rose_state2_machine(sk, skb, frametype);
+			break;
+		case ROSE_STATE_3:
+			queued = rose_state3_machine(sk, skb, frametype, ns, nr, q, d, m);
+			break;
+		case ROSE_STATE_4:
+			queued = rose_state4_machine(sk, skb, frametype);
+			break;
+		case ROSE_STATE_5:
+			queued = rose_state5_machine(sk, skb, frametype);
+			break;
+	}
+
+	rose_set_timer(sk);
+
+	return queued;
+}
+
+#endif