--- /dev/null
+/*
+ * Generic HDLC support routines for Linux
+ * X.25 support
+ *
+ * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ */
+
+#include <linux/errno.h>
+#include <linux/gfp.h>
+#include <linux/hdlc.h>
+#include <linux/if_arp.h>
+#include <linux/inetdevice.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/lapb.h>
+#include <linux/module.h>
+#include <linux/pkt_sched.h>
+#include <linux/poll.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+#include <net/x25device.h>
+
+static int x25_ioctl(struct net_device *dev, struct ifreq *ifr);
+
+/* These functions are callbacks called by LAPB layer */
+
+static void x25_connect_disconnect(struct net_device *dev, int reason, int code)
+{
+ struct sk_buff *skb;
+ unsigned char *ptr;
+
+ if ((skb = dev_alloc_skb(1)) == NULL) {
+ netdev_err(dev, "out of memory\n");
+ return;
+ }
+
+ ptr = skb_put(skb, 1);
+ *ptr = code;
+
+ skb->protocol = x25_type_trans(skb, dev);
+ netif_rx(skb);
+}
+
+
+
+static void x25_connected(struct net_device *dev, int reason)
+{
+ x25_connect_disconnect(dev, reason, X25_IFACE_CONNECT);
+}
+
+
+
+static void x25_disconnected(struct net_device *dev, int reason)
+{
+ x25_connect_disconnect(dev, reason, X25_IFACE_DISCONNECT);
+}
+
+
+
+static int x25_data_indication(struct net_device *dev, struct sk_buff *skb)
+{
+ unsigned char *ptr;
+
+ skb_push(skb, 1);
+
+ if (skb_cow(skb, 1))
+ return NET_RX_DROP;
+
+ ptr = skb->data;
+ *ptr = X25_IFACE_DATA;
+
+ skb->protocol = x25_type_trans(skb, dev);
+ return netif_rx(skb);
+}
+
+
+
+static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb)
+{
+ hdlc_device *hdlc = dev_to_hdlc(dev);
+ hdlc->xmit(skb, dev); /* Ignore return value :-( */
+}
+
+
+
+static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ int result;
+
+
+ /* X.25 to LAPB */
+ switch (skb->data[0]) {
+ case X25_IFACE_DATA: /* Data to be transmitted */
+ skb_pull(skb, 1);
+ if ((result = lapb_data_request(dev, skb)) != LAPB_OK)
+ dev_kfree_skb(skb);
+ return NETDEV_TX_OK;
+
+ case X25_IFACE_CONNECT:
+ if ((result = lapb_connect_request(dev))!= LAPB_OK) {
+ if (result == LAPB_CONNECTED)
+ /* Send connect confirm. msg to level 3 */
+ x25_connected(dev, 0);
+ else
+ netdev_err(dev, "LAPB connect request failed, error code = %i\n",
+ result);
+ }
+ break;
+
+ case X25_IFACE_DISCONNECT:
+ if ((result = lapb_disconnect_request(dev)) != LAPB_OK) {
+ if (result == LAPB_NOTCONNECTED)
+ /* Send disconnect confirm. msg to level 3 */
+ x25_disconnected(dev, 0);
+ else
+ netdev_err(dev, "LAPB disconnect request failed, error code = %i\n",
+ result);
+ }
+ break;
+
+ default: /* to be defined */
+ break;
+ }
+
+ dev_kfree_skb(skb);
+ return NETDEV_TX_OK;
+}
+
+
+
+static int x25_open(struct net_device *dev)
+{
+ int result;
+ static const struct lapb_register_struct cb = {
+ .connect_confirmation = x25_connected,
+ .connect_indication = x25_connected,
+ .disconnect_confirmation = x25_disconnected,
+ .disconnect_indication = x25_disconnected,
+ .data_indication = x25_data_indication,
+ .data_transmit = x25_data_transmit,
+ };
+
+ result = lapb_register(dev, &cb);
+ if (result != LAPB_OK)
+ return result;
+ return 0;
+}
+
+
+
+static void x25_close(struct net_device *dev)
+{
+ lapb_unregister(dev);
+}
+
+
+
+static int x25_rx(struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+
+ if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
+ dev->stats.rx_dropped++;
+ return NET_RX_DROP;
+ }
+
+ if (lapb_data_received(dev, skb) == LAPB_OK)
+ return NET_RX_SUCCESS;
+
+ dev->stats.rx_errors++;
+ dev_kfree_skb_any(skb);
+ return NET_RX_DROP;
+}
+
+
+static struct hdlc_proto proto = {
+ .open = x25_open,
+ .close = x25_close,
+ .ioctl = x25_ioctl,
+ .netif_rx = x25_rx,
+ .xmit = x25_xmit,
+ .module = THIS_MODULE,
+};
+
+
+static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
+{
+ hdlc_device *hdlc = dev_to_hdlc(dev);
+ int result;
+
+ switch (ifr->ifr_settings.type) {
+ case IF_GET_PROTO:
+ if (dev_to_hdlc(dev)->proto != &proto)
+ return -EINVAL;
+ ifr->ifr_settings.type = IF_PROTO_X25;
+ return 0; /* return protocol only, no settable parameters */
+
+ case IF_PROTO_X25:
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
+ if (dev->flags & IFF_UP)
+ return -EBUSY;
+
+ result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
+ if (result)
+ return result;
+
+ if ((result = attach_hdlc_protocol(dev, &proto, 0)))
+ return result;
+ dev->type = ARPHRD_X25;
+ netif_dormant_off(dev);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+
+static int __init mod_init(void)
+{
+ register_hdlc_protocol(&proto);
+ return 0;
+}
+
+
+
+static void __exit mod_exit(void)
+{
+ unregister_hdlc_protocol(&proto);
+}
+
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
+MODULE_DESCRIPTION("X.25 protocol support for generic HDLC");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff