/* * Generic HDLC support routines for Linux * * Copyright (C) 1999 - 2005 Krzysztof Halasa * * 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. * * Currently supported: * * raw IP-in-HDLC * * Cisco HDLC * * Frame Relay with ANSI or CCITT LMI (both user and network side) * * PPP * * X.25 * * Use sethdlc utility to set line parameters, protocol and PVCs * * How does it work: * - proto.open(), close(), start(), stop() calls are serialized. * The order is: open, [ start, stop ... ] close ... * - proto.start() and stop() are called with spin_lock_irq held. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include static const char* version = "HDLC support module revision 1.19"; #undef DEBUG_LINK static int hdlc_change_mtu(struct net_device *dev, int new_mtu) { if ((new_mtu < 68) || (new_mtu > HDLC_MAX_MTU)) return -EINVAL; dev->mtu = new_mtu; return 0; } static struct net_device_stats *hdlc_get_stats(struct net_device *dev) { return hdlc_stats(dev); } static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *p, struct net_device *orig_dev) { hdlc_device *hdlc = dev_to_hdlc(dev); if (hdlc->proto.netif_rx) return hdlc->proto.netif_rx(skb); hdlc->stats.rx_dropped++; /* Shouldn't happen */ dev_kfree_skb(skb); return NET_RX_DROP; } static inline void hdlc_proto_start(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); if (hdlc->proto.start) return hdlc->proto.start(dev); } static inline void hdlc_proto_stop(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); if (hdlc->proto.stop) return hdlc->proto.stop(dev); } static int hdlc_device_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = ptr; hdlc_device *hdlc; unsigned long flags; int on; if (dev->get_stats != hdlc_get_stats) return NOTIFY_DONE; /* not an HDLC device */ if (event != NETDEV_CHANGE) return NOTIFY_DONE; /* Only interrested in carrier changes */ on = netif_carrier_ok(dev); #ifdef DEBUG_LINK printk(KERN_DEBUG "%s: hdlc_device_event NETDEV_CHANGE, carrier %i\n", dev->name, on); #endif hdlc = dev_to_hdlc(dev); spin_lock_irqsave(&hdlc->state_lock, flags); if (hdlc->carrier == on) goto carrier_exit; /* no change in DCD line level */ hdlc->carrier = on; if (!hdlc->open) goto carrier_exit; if (hdlc->carrier) { printk(KERN_INFO "%s: Carrier detected\n", dev->name); hdlc_proto_start(dev); } else { printk(KERN_INFO "%s: Carrier lost\n", dev->name); hdlc_proto_stop(dev); } carrier_exit: spin_unlock_irqrestore(&hdlc->state_lock, flags); return NOTIFY_DONE; } /* Must be called by hardware driver when HDLC device is being opened */ int hdlc_open(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); #ifdef DEBUG_LINK printk(KERN_DEBUG "hdlc_open() carrier %i open %i\n", hdlc->carrier, hdlc->open); #endif if (hdlc->proto.id == -1) return -ENOSYS; /* no protocol attached */ if (hdlc->proto.open) { int result = hdlc->proto.open(dev); if (result) return result; } spin_lock_irq(&hdlc->state_lock); if (hdlc->carrier) { printk(KERN_INFO "%s: Carrier detected\n", dev->name); hdlc_proto_start(dev); } else printk(KERN_INFO "%s: No carrier\n", dev->name); hdlc->open = 1; spin_unlock_irq(&hdlc->state_lock); return 0; } /* Must be called by hardware driver when HDLC device is being closed */ void hdlc_close(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); #ifdef DEBUG_LINK printk(KERN_DEBUG "hdlc_close() carrier %i open %i\n", hdlc->carrier, hdlc->open); #endif spin_lock_irq(&hdlc->state_lock); hdlc->open = 0; if (hdlc->carrier) hdlc_proto_stop(dev); spin_unlock_irq(&hdlc->state_lock); if (hdlc->proto.close) hdlc->proto.close(dev); } #ifndef CONFIG_HDLC_RAW #define hdlc_raw_ioctl(dev, ifr) -ENOSYS #endif #ifndef CONFIG_HDLC_RAW_ETH #define hdlc_raw_eth_ioctl(dev, ifr) -ENOSYS #endif #ifndef CONFIG_HDLC_PPP #define hdlc_ppp_ioctl(dev, ifr) -ENOSYS #endif #ifndef CONFIG_HDLC_CISCO #define hdlc_cisco_ioctl(dev, ifr) -ENOSYS #endif #ifndef CONFIG_HDLC_FR #define hdlc_fr_ioctl(dev, ifr) -ENOSYS #endif #ifndef CONFIG_HDLC_X25 #define hdlc_x25_ioctl(dev, ifr) -ENOSYS #endif int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) { hdlc_device *hdlc = dev_to_hdlc(dev); unsigned int proto; if (cmd != SIOCWANDEV) return -EINVAL; switch(ifr->ifr_settings.type) { case IF_PROTO_HDLC: case IF_PROTO_HDLC_ETH: case IF_PROTO_PPP: case IF_PROTO_CISCO: case IF_PROTO_FR: case IF_PROTO_X25: proto = ifr->ifr_settings.type; break; default: proto = hdlc->proto.id; } switch(proto) { case IF_PROTO_HDLC: return hdlc_raw_ioctl(dev, ifr); case IF_PROTO_HDLC_ETH: return hdlc_raw_eth_ioctl(dev, ifr); case IF_PROTO_PPP: return hdlc_ppp_ioctl(dev, ifr); case IF_PROTO_CISCO: return hdlc_cisco_ioctl(dev, ifr); case IF_PROTO_FR: return hdlc_fr_ioctl(dev, ifr); case IF_PROTO_X25: return hdlc_x25_ioctl(dev, ifr); default: return -EINVAL; } } void hdlc_setup(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); dev->get_stats = hdlc_get_stats; dev->change_mtu = hdlc_change_mtu; dev->mtu = HDLC_MAX_MTU; dev->type = ARPHRD_RAWHDLC; dev->hard_header_len = 16; dev->flags = IFF_POINTOPOINT | IFF_NOARP; hdlc->proto.id = -1; hdlc->proto.detach = NULL; hdlc->carrier = 1; hdlc->open = 0; spin_lock_init(&hdlc->state_lock); } struct net_device *alloc_hdlcdev(void *priv) { struct net_device *dev; dev = alloc_netdev(sizeof(hdlc_device), "hdlc%d", hdlc_setup); if (dev) dev_to_hdlc(dev)->priv = priv; return dev; } void unregister_hdlc_device(struct net_device *dev) { rtnl_lock(); hdlc_proto_detach(dev_to_hdlc(dev)); unregister_netdevice(dev); rtnl_unlock(); } MODULE_AUTHOR("Krzysztof Halasa "); MODULE_DESCRIPTION("HDLC support module"); MODULE_LICENSE("GPL v2"); EXPORT_SYMBOL(hdlc_open); EXPORT_SYMBOL(hdlc_close); EXPORT_SYMBOL(hdlc_ioctl); EXPORT_SYMBOL(hdlc_setup); EXPORT_SYMBOL(alloc_hdlcdev); EXPORT_SYMBOL(unregister_hdlc_device); static struct packet_type hdlc_packet_type = { .type = __constant_htons(ETH_P_HDLC), .func = hdlc_rcv, }; static struct notifier_block hdlc_notifier = { .notifier_call = hdlc_device_event, }; static int __init hdlc_module_init(void) { int result; printk(KERN_INFO "%s\n", version); if ((result = register_netdevice_notifier(&hdlc_notifier)) != 0) return result; dev_add_pack(&hdlc_packet_type); return 0; } static void __exit hdlc_module_exit(void) { dev_remove_pack(&hdlc_packet_type); unregister_netdevice_notifier(&hdlc_notifier); } module_init(hdlc_module_init); module_exit(hdlc_module_exit);