/* * Generic HDLC support routines for Linux * Point-to-point protocol support * * Copyright (C) 1999 - 2003 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>static int ppp_open(struct net_device *dev){	hdlc_device *hdlc = dev_to_hdlc(dev);	void *old_ioctl;	int result;	dev->priv = &hdlc->state.ppp.syncppp_ptr;	hdlc->state.ppp.syncppp_ptr = &hdlc->state.ppp.pppdev;	hdlc->state.ppp.pppdev.dev = dev;	old_ioctl = dev->do_ioctl;	hdlc->state.ppp.old_change_mtu = dev->change_mtu;	sppp_attach(&hdlc->state.ppp.pppdev);	/* sppp_attach nukes them. We don't need syncppp's ioctl */	dev->do_ioctl = old_ioctl;	hdlc->state.ppp.pppdev.sppp.pp_flags &= ~PP_CISCO;	dev->type = ARPHRD_PPP;	result = sppp_open(dev);	if (result) {		sppp_detach(dev);		return result;	}	return 0;}static void ppp_close(struct net_device *dev){	hdlc_device *hdlc = dev_to_hdlc(dev);	sppp_close(dev);	sppp_detach(dev);	dev->rebuild_header = NULL;	dev->change_mtu = hdlc->state.ppp.old_change_mtu;	dev->mtu = HDLC_MAX_MTU;	dev->hard_header_len = 16;}static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev){	return __constant_htons(ETH_P_WAN_PPP);}int hdlc_ppp_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:		ifr->ifr_settings.type = IF_PROTO_PPP;		return 0; /* return protocol only, no settable parameters */	case IF_PROTO_PPP:		if(!capable(CAP_NET_ADMIN))			return -EPERM;		if(dev->flags & IFF_UP)			return -EBUSY;		/* no settable parameters */		result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);		if (result)			return result;		hdlc_proto_detach(hdlc);		memset(&hdlc->proto, 0, sizeof(hdlc->proto));		hdlc->proto.open = ppp_open;		hdlc->proto.close = ppp_close;		hdlc->proto.type_trans = ppp_type_trans;		hdlc->proto.id = IF_PROTO_PPP;		dev->hard_start_xmit = hdlc->xmit;		dev->hard_header = NULL;		dev->type = ARPHRD_PPP;		dev->addr_len = 0;		return 0;	}	return -EINVAL;}