patch-2.1.9 linux/net/rose/rose_out

• Lines: 255
• Date: Sun Nov 10 19:12:58 1996
• Orig file: v2.1.8/linux/net/rose/rose_out
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v2.1.8/linux/net/rose/rose_out linux/net/rose/rose_out
@@ -0,0 +1,254 @@
+/*
+ *	Rose release 001
+ *
+ *	This is ALPHA test software. This code may break your machine, randomly fail to work with new 
+ *	releases, misbehave and/or generally screw up. It might even work. 
+ *
+ *	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.
+ *
+ *	History
+ *	Rose 001	Jonathan(G4KLX)	Cloned from nr_out.c
+ */
+
+#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 <asm/segment.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/rose.h>
+
+/*
+ *	This is where all Rose frames pass;
+ */
+void rose_output(struct sock *sk, struct sk_buff *skb)
+{
+	struct sk_buff *skbn;
+	unsigned char header[ROSE_MIN_LEN];
+	int err, frontlen, len;
+
+	if (skb->len - ROSE_MIN_LEN > ROSE_PACLEN) {
+		/* Save a copy of the Header */
+		memcpy(header, skb->data, ROSE_MIN_LEN);
+		skb_pull(skb, ROSE_MIN_LEN);
+
+		frontlen = skb_headroom(skb);
+
+		while (skb->len > 0) {
+			if ((skbn = sock_alloc_send_skb(sk, frontlen + ROSE_PACLEN, 0, 0, &err)) == NULL)
+				return;
+
+			skbn->sk   = sk;
+			skbn->free = 1;
+			skbn->arp  = 1;
+
+			skb_reserve(skbn, frontlen);
+
+			len = (ROSE_PACLEN > skb->len) ? skb->len : ROSE_PACLEN;
+
+			/* Copy the user data */
+			memcpy(skb_put(skbn, len), skb->data, len);
+			skb_pull(skb, len);
+
+			/* Duplicate the Header */
+			skb_push(skbn, ROSE_MIN_LEN);
+			memcpy(skbn->data, header, ROSE_MIN_LEN);
+
+			if (skb->len > 0)
+				skbn->data[2] |= M_BIT;
+		
+			skb_queue_tail(&sk->write_queue, skbn); /* Throw it on the queue */
+		}
+		
+		skb->free = 1;
+		kfree_skb(skb, FREE_WRITE);
+	} else {
+		skb_queue_tail(&sk->write_queue, skb);		/* Throw it on the queue */
+	}
+
+	if (sk->protinfo.rose->state == ROSE_STATE_3)
+		rose_kick(sk);
+}
+
+/* 
+ *	This procedure is passed a buffer descriptor for an iframe. It builds
+ *	the rest of the control part of the frame and then writes it out.
+ */
+static void rose_send_iframe(struct sock *sk, struct sk_buff *skb, int last)
+{
+	if (skb == NULL)
+		return;
+
+	if (last)
+		skb->data[0] |= D_BIT;
+
+	skb->data[2] |= (sk->protinfo.rose->vr << 5) & 0xE0;
+	skb->data[2] |= (sk->protinfo.rose->vs << 1) & 0x0E;
+
+	rose_transmit_buffer(sk, skb);	
+}
+
+void rose_send_nak_frame(struct sock *sk)
+{
+	struct sk_buff *skb, *skbn;
+	
+	if ((skb = skb_peek(&sk->protinfo.rose->ack_queue)) == NULL)
+		return;
+		
+	if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL)
+		return;
+
+	skbn->data[2] = sk->protinfo.rose->va;
+	skbn->data[3] = sk->protinfo.rose->vr;
+
+	if (sk->protinfo.rose->condition & OWN_RX_BUSY_CONDITION)
+		skbn->data[4] |= NR_CHOKE_FLAG;
+
+	rose_transmit_buffer(sk, skbn);
+
+	sk->protinfo.rose->condition &= ~ACK_PENDING_CONDITION;
+	sk->protinfo.rose->vl      = sk->protinfo.rose->vr;
+	sk->protinfo.rose->t1timer = 0;
+}
+
+void rose_kick(struct sock *sk)
+{
+	struct sk_buff *skb, *skbn;
+	int last = 1;
+	unsigned short start, end, next;
+
+	del_timer(&sk->timer);
+
+	start = (skb_peek(&sk->protinfo.rose->ack_queue) == NULL) ? sk->protinfo.rose->va : sk->protinfo.rose->vs;
+	end   = (sk->protinfo.rose->va + sk->window) % ROSE_MODULUS;
+
+	if (!(sk->protinfo.rose->condition & PEER_RX_BUSY_CONDITION) &&
+	    start != end                                  &&
+	    skb_peek(&sk->write_queue) != NULL) {
+
+		sk->protinfo.rose->vs = start;
+
+		/*
+		 * Transmit data until either we're out of data to send or
+		 * the window is full.
+		 */
+
+		/*
+		 * Dequeue the frame and copy it.
+		 */
+		skb  = skb_dequeue(&sk->write_queue);
+
+		do {
+			if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
+				skb_queue_head(&sk->write_queue, skb);
+				break;
+			}
+
+			next = (sk->protinfo.rose->vs + 1) % ROSE_MODULUS;
+			last = (next == end);
+
+			/*
+			 * Transmit the frame copy.
+			 */
+			rose_send_iframe(sk, skbn, last);
+
+			sk->protinfo.rose->vs = next;
+
+			/*
+			 * Requeue the original data frame.
+			 */
+			skb_queue_tail(&sk->protinfo.rose->ack_queue, skb);
+
+		} while (!last && (skb = skb_dequeue(&sk->write_queue)) != NULL);
+
+		sk->protinfo.rose->vl = sk->protinfo.rose->vr;
+		sk->protinfo.rose->condition &= ~ACK_PENDING_CONDITION;
+	}
+
+	rose_set_timer(sk);
+}
+
+void rose_transmit_buffer(struct sock *sk, struct sk_buff *skb)
+{
+	unsigned char *dptr;
+
+	dptr  = skb_push(skb, 1);
+	*dptr = AX25_P_ROSE;
+
+	skb->arp = 1;
+
+	if (!ax25_send_frame(skb, (ax25_address *)sk->protinfo.rose->neighbour->dev->dev_addr, &sk->protinfo.rose->neighbour->callsign, sk->protinfo.rose->neighbour->digipeat, sk->protinfo.rose->neighbour->dev)) {
+		kfree_skb(skb, FREE_WRITE);
+
+		sk->state = TCP_CLOSE;
+		sk->err   = ENETUNREACH;
+		if (!sk->dead)
+			sk->state_change(sk);
+		sk->dead  = 1;
+	}
+}
+
+/*
+ * The following routines are taken from page 170 of the 7th ARRL Computer
+ * Networking Conference paper, as is the whole state machine.
+ */
+
+void rose_establish_data_link(struct sock *sk)
+{
+	sk->protinfo.rose->condition = 0x00;
+
+	rose_write_internal(sk, ROSE_CALL_REQUEST);
+
+	sk->protinfo.rose->t1timer = sk->protinfo.rose->t1;
+}
+
+/*
+ * Never send a NAK when we are CHOKEd.
+ */
+void rose_enquiry_response(struct sock *sk)
+{
+	int frametype = NR_INFOACK;
+	
+	if (sk->protinfo.rose->condition & OWN_RX_BUSY_CONDITION)
+		frametype |= NR_CHOKE_FLAG;
+	
+	rose_write_internal(sk, frametype);
+
+	sk->protinfo.rose->vl = sk->protinfo.rose->vr;
+	sk->protinfo.rose->condition &= ~ACK_PENDING_CONDITION;
+}
+
+void rose_check_iframes_acked(struct sock *sk, unsigned short nr)
+{
+	if (sk->protinfo.rose->vs == nr) {
+		rose_frames_acked(sk, nr);
+	} else {
+		if (sk->protinfo.rose->va != nr) {
+			rose_frames_acked(sk, nr);
+		}
+	}
+}
+
+#endif