/* * 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/module.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/poll.h> #include <linux/errno.h> #include <linux/if_arp.h> #include <linux/init.h> #include <linux/skbuff.h> #include <linux/pkt_sched.h> #include <linux/inetdevice.h> #include <linux/lapb.h> #include <linux/rtnetlink.h> #include <linux/hdlc.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) { printk(KERN_ERR "%s: out of memory\n", dev->name); 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, 1); } static void x25_disconnected(struct net_device *dev, int reason) { x25_connect_disconnect(dev, reason, 2); } 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 = 0; 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 int x25_xmit(struct sk_buff *skb, struct net_device *dev) { int result; /* X.25 to LAPB */ switch (skb->data[0]) { case 0: /* Data to be transmitted */ skb_pull(skb, 1); if ((result = lapb_data_request(dev, skb)) != LAPB_OK) dev_kfree_skb(skb); return 0; case 1: if ((result = lapb_connect_request(dev))!= LAPB_OK) { if (result == LAPB_CONNECTED) /* Send connect confirm. msg to level 3 */ x25_connected(dev, 0); else printk(KERN_ERR "%s: LAPB connect request " "failed, error code = %i\n", dev->name, result); } break; case 2: if ((result = lapb_disconnect_request(dev)) != LAPB_OK) { if (result == LAPB_NOTCONNECTED) /* Send disconnect confirm. msg to level 3 */ x25_disconnected(dev, 0); else printk(KERN_ERR "%s: LAPB disconnect request " "failed, error code = %i\n", dev->name, result); } break; default: /* to be defined */ break; } dev_kfree_skb(skb); return 0; } static int x25_open(struct net_device *dev) { struct lapb_register_struct cb; int result; cb.connect_confirmation = x25_connected; cb.connect_indication = x25_connected; cb.disconnect_confirmation = x25_disconnected; cb.disconnect_indication = x25_disconnected; cb.data_indication = x25_data_indication; cb.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 hdlc_device *hdlc = dev_to_hdlc(skb->dev); if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) { hdlc->stats.rx_dropped++; return NET_RX_DROP; } if (lapb_data_received(skb->dev, skb) == LAPB_OK) return NET_RX_SUCCESS; hdlc->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, .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->hard_start_xmit = x25_xmit; 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");