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-rw-r--r--net/rose/rose_link.c289
1 files changed, 289 insertions, 0 deletions
diff --git a/net/rose/rose_link.c b/net/rose/rose_link.c
new file mode 100644
index 0000000000..0f77ae8ef9
--- /dev/null
+++ b/net/rose/rose_link.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/rose.h>
+
+static void rose_ftimer_expiry(struct timer_list *);
+static void rose_t0timer_expiry(struct timer_list *);
+
+static void rose_transmit_restart_confirmation(struct rose_neigh *neigh);
+static void rose_transmit_restart_request(struct rose_neigh *neigh);
+
+void rose_start_ftimer(struct rose_neigh *neigh)
+{
+ del_timer(&neigh->ftimer);
+
+ neigh->ftimer.function = rose_ftimer_expiry;
+ neigh->ftimer.expires =
+ jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout);
+
+ add_timer(&neigh->ftimer);
+}
+
+static void rose_start_t0timer(struct rose_neigh *neigh)
+{
+ del_timer(&neigh->t0timer);
+
+ neigh->t0timer.function = rose_t0timer_expiry;
+ neigh->t0timer.expires =
+ jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout);
+
+ add_timer(&neigh->t0timer);
+}
+
+void rose_stop_ftimer(struct rose_neigh *neigh)
+{
+ del_timer(&neigh->ftimer);
+}
+
+void rose_stop_t0timer(struct rose_neigh *neigh)
+{
+ del_timer(&neigh->t0timer);
+}
+
+int rose_ftimer_running(struct rose_neigh *neigh)
+{
+ return timer_pending(&neigh->ftimer);
+}
+
+static int rose_t0timer_running(struct rose_neigh *neigh)
+{
+ return timer_pending(&neigh->t0timer);
+}
+
+static void rose_ftimer_expiry(struct timer_list *t)
+{
+}
+
+static void rose_t0timer_expiry(struct timer_list *t)
+{
+ struct rose_neigh *neigh = from_timer(neigh, t, t0timer);
+
+ rose_transmit_restart_request(neigh);
+
+ neigh->dce_mode = 0;
+
+ rose_start_t0timer(neigh);
+}
+
+/*
+ * Interface to ax25_send_frame. Changes my level 2 callsign depending
+ * on whether we have a global ROSE callsign or use the default port
+ * callsign.
+ */
+static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
+{
+ const ax25_address *rose_call;
+ ax25_cb *ax25s;
+
+ if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
+ rose_call = (const ax25_address *)neigh->dev->dev_addr;
+ else
+ rose_call = &rose_callsign;
+
+ ax25s = neigh->ax25;
+ neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
+ if (ax25s)
+ ax25_cb_put(ax25s);
+
+ return neigh->ax25 != NULL;
+}
+
+/*
+ * Interface to ax25_link_up. Changes my level 2 callsign depending
+ * on whether we have a global ROSE callsign or use the default port
+ * callsign.
+ */
+static int rose_link_up(struct rose_neigh *neigh)
+{
+ const ax25_address *rose_call;
+ ax25_cb *ax25s;
+
+ if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
+ rose_call = (const ax25_address *)neigh->dev->dev_addr;
+ else
+ rose_call = &rose_callsign;
+
+ ax25s = neigh->ax25;
+ neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
+ if (ax25s)
+ ax25_cb_put(ax25s);
+
+ return neigh->ax25 != NULL;
+}
+
+/*
+ * This handles all restart and diagnostic frames.
+ */
+void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype)
+{
+ struct sk_buff *skbn;
+
+ switch (frametype) {
+ case ROSE_RESTART_REQUEST:
+ rose_stop_t0timer(neigh);
+ neigh->restarted = 1;
+ neigh->dce_mode = (skb->data[3] == ROSE_DTE_ORIGINATED);
+ rose_transmit_restart_confirmation(neigh);
+ break;
+
+ case ROSE_RESTART_CONFIRMATION:
+ rose_stop_t0timer(neigh);
+ neigh->restarted = 1;
+ break;
+
+ case ROSE_DIAGNOSTIC:
+ pr_warn("ROSE: received diagnostic #%d - %3ph\n", skb->data[3],
+ skb->data + 4);
+ break;
+
+ default:
+ printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
+ break;
+ }
+
+ if (neigh->restarted) {
+ while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
+ if (!rose_send_frame(skbn, neigh))
+ kfree_skb(skbn);
+ }
+}
+
+/*
+ * This routine is called when a Restart Request is needed
+ */
+static void rose_transmit_restart_request(struct rose_neigh *neigh)
+{
+ struct sk_buff *skb;
+ unsigned char *dptr;
+ int len;
+
+ len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
+
+ if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+ return;
+
+ skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
+
+ dptr = skb_put(skb, ROSE_MIN_LEN + 3);
+
+ *dptr++ = AX25_P_ROSE;
+ *dptr++ = ROSE_GFI;
+ *dptr++ = 0x00;
+ *dptr++ = ROSE_RESTART_REQUEST;
+ *dptr++ = ROSE_DTE_ORIGINATED;
+ *dptr++ = 0;
+
+ if (!rose_send_frame(skb, neigh))
+ kfree_skb(skb);
+}
+
+/*
+ * This routine is called when a Restart Confirmation is needed
+ */
+static void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
+{
+ struct sk_buff *skb;
+ unsigned char *dptr;
+ int len;
+
+ len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
+
+ if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+ return;
+
+ skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
+
+ dptr = skb_put(skb, ROSE_MIN_LEN + 1);
+
+ *dptr++ = AX25_P_ROSE;
+ *dptr++ = ROSE_GFI;
+ *dptr++ = 0x00;
+ *dptr++ = ROSE_RESTART_CONFIRMATION;
+
+ if (!rose_send_frame(skb, neigh))
+ kfree_skb(skb);
+}
+
+/*
+ * This routine is called when a Clear Request is needed outside of the context
+ * of a connected socket.
+ */
+void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
+{
+ struct sk_buff *skb;
+ unsigned char *dptr;
+ int len;
+
+ if (!neigh->dev)
+ return;
+
+ len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
+
+ if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+ return;
+
+ skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
+
+ dptr = skb_put(skb, ROSE_MIN_LEN + 3);
+
+ *dptr++ = AX25_P_ROSE;
+ *dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI;
+ *dptr++ = ((lci >> 0) & 0xFF);
+ *dptr++ = ROSE_CLEAR_REQUEST;
+ *dptr++ = cause;
+ *dptr++ = diagnostic;
+
+ if (!rose_send_frame(skb, neigh))
+ kfree_skb(skb);
+}
+
+void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh)
+{
+ unsigned char *dptr;
+
+ if (neigh->loopback) {
+ rose_loopback_queue(skb, neigh);
+ return;
+ }
+
+ if (!rose_link_up(neigh))
+ neigh->restarted = 0;
+
+ dptr = skb_push(skb, 1);
+ *dptr++ = AX25_P_ROSE;
+
+ if (neigh->restarted) {
+ if (!rose_send_frame(skb, neigh))
+ kfree_skb(skb);
+ } else {
+ skb_queue_tail(&neigh->queue, skb);
+
+ if (!rose_t0timer_running(neigh)) {
+ rose_transmit_restart_request(neigh);
+ neigh->dce_mode = 0;
+ rose_start_t0timer(neigh);
+ }
+ }
+}
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