Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1488 insertions, 0 deletions

diff --git a/drivers/net/wan/syncppp.c b/drivers/net/wan/syncppp.c
new file mode 100644
index 0000000..84b65c6
--- /dev/null
+++ b/drivers/net/wan/syncppp.c
@@ -0,0 +1,1488 @@
+/*
+ *	NET3:	A (fairly minimal) implementation of synchronous PPP for Linux
+ *		as well as a CISCO HDLC implementation. See the copyright 
+ *		message below for the original source.
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the license, or (at your option) any later version.
+ *
+ *	Note however. This code is also used in a different form by FreeBSD.
+ *	Therefore when making any non OS specific change please consider
+ *	contributing it back to the original author under the terms
+ *	below in addition.
+ *		-- Alan
+ *
+ *	Port for Linux-2.1 by Jan "Yenya" Kasprzak <kas@fi.muni.cz>
+ */
+
+/*
+ * Synchronous PPP/Cisco link level subroutines.
+ * Keepalive protocol implemented in both Cisco and PPP modes.
+ *
+ * Copyright (C) 1994 Cronyx Ltd.
+ * Author: Serge Vakulenko, <vak@zebub.msk.su>
+ *
+ * This software is distributed with NO WARRANTIES, not even the implied
+ * warranties for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Authors grant any other persons or organisations permission to use
+ * or modify this software as long as this message is kept with the software,
+ * all derivative works or modified versions.
+ *
+ * Version 1.9, Wed Oct  4 18:58:15 MSK 1995
+ *
+ * $Id: syncppp.c,v 1.18 2000/04/11 05:25:31 asj Exp $
+ */
+#undef DEBUG
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <linux/route.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/random.h>
+#include <linux/pkt_sched.h>
+#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
+
+#include <net/syncppp.h>
+
+#include <asm/byteorder.h>
+#include <asm/uaccess.h>
+
+#define MAXALIVECNT     6               /* max. alive packets */
+
+#define PPP_ALLSTATIONS 0xff            /* All-Stations broadcast address */
+#define PPP_UI          0x03            /* Unnumbered Information */
+#define PPP_IP          0x0021          /* Internet Protocol */
+#define PPP_ISO         0x0023          /* ISO OSI Protocol */
+#define PPP_XNS         0x0025          /* Xerox NS Protocol */
+#define PPP_IPX         0x002b          /* Novell IPX Protocol */
+#define PPP_LCP         0xc021          /* Link Control Protocol */
+#define PPP_IPCP        0x8021          /* Internet Protocol Control Protocol */
+
+#define LCP_CONF_REQ    1               /* PPP LCP configure request */
+#define LCP_CONF_ACK    2               /* PPP LCP configure acknowledge */
+#define LCP_CONF_NAK    3               /* PPP LCP configure negative ack */
+#define LCP_CONF_REJ    4               /* PPP LCP configure reject */
+#define LCP_TERM_REQ    5               /* PPP LCP terminate request */
+#define LCP_TERM_ACK    6               /* PPP LCP terminate acknowledge */
+#define LCP_CODE_REJ    7               /* PPP LCP code reject */
+#define LCP_PROTO_REJ   8               /* PPP LCP protocol reject */
+#define LCP_ECHO_REQ    9               /* PPP LCP echo request */
+#define LCP_ECHO_REPLY  10              /* PPP LCP echo reply */
+#define LCP_DISC_REQ    11              /* PPP LCP discard request */
+
+#define LCP_OPT_MRU             1       /* maximum receive unit */
+#define LCP_OPT_ASYNC_MAP       2       /* async control character map */
+#define LCP_OPT_AUTH_PROTO      3       /* authentication protocol */
+#define LCP_OPT_QUAL_PROTO      4       /* quality protocol */
+#define LCP_OPT_MAGIC           5       /* magic number */
+#define LCP_OPT_RESERVED        6       /* reserved */
+#define LCP_OPT_PROTO_COMP      7       /* protocol field compression */
+#define LCP_OPT_ADDR_COMP       8       /* address/control field compression */
+
+#define IPCP_CONF_REQ   LCP_CONF_REQ    /* PPP IPCP configure request */
+#define IPCP_CONF_ACK   LCP_CONF_ACK    /* PPP IPCP configure acknowledge */
+#define IPCP_CONF_NAK   LCP_CONF_NAK    /* PPP IPCP configure negative ack */
+#define IPCP_CONF_REJ   LCP_CONF_REJ    /* PPP IPCP configure reject */
+#define IPCP_TERM_REQ   LCP_TERM_REQ    /* PPP IPCP terminate request */
+#define IPCP_TERM_ACK   LCP_TERM_ACK    /* PPP IPCP terminate acknowledge */
+#define IPCP_CODE_REJ   LCP_CODE_REJ    /* PPP IPCP code reject */
+
+#define CISCO_MULTICAST         0x8f    /* Cisco multicast address */
+#define CISCO_UNICAST           0x0f    /* Cisco unicast address */
+#define CISCO_KEEPALIVE         0x8035  /* Cisco keepalive protocol */
+#define CISCO_ADDR_REQ          0       /* Cisco address request */
+#define CISCO_ADDR_REPLY        1       /* Cisco address reply */
+#define CISCO_KEEPALIVE_REQ     2       /* Cisco keepalive request */
+
+struct ppp_header {
+	u8 address;
+	u8 control;
+	u16 protocol;
+};
+#define PPP_HEADER_LEN          sizeof (struct ppp_header)
+
+struct lcp_header {
+	u8 type;
+	u8 ident;
+	u16 len;
+};
+#define LCP_HEADER_LEN          sizeof (struct lcp_header)
+
+struct cisco_packet {
+	u32 type;
+	u32 par1;
+	u32 par2;
+	u16 rel;
+	u16 time0;
+	u16 time1;
+};
+#define CISCO_PACKET_LEN 18
+#define CISCO_BIG_PACKET_LEN 20
+
+static struct sppp *spppq;
+static struct timer_list sppp_keepalive_timer;
+static DEFINE_SPINLOCK(spppq_lock);
+
+/* global xmit queue for sending packets while spinlock is held */
+static struct sk_buff_head tx_queue;
+
+static void sppp_keepalive (unsigned long dummy);
+static void sppp_cp_send (struct sppp *sp, u16 proto, u8 type,
+	u8 ident, u16 len, void *data);
+static void sppp_cisco_send (struct sppp *sp, int type, long par1, long par2);
+static void sppp_lcp_input (struct sppp *sp, struct sk_buff *m);
+static void sppp_cisco_input (struct sppp *sp, struct sk_buff *m);
+static void sppp_ipcp_input (struct sppp *sp, struct sk_buff *m);
+static void sppp_lcp_open (struct sppp *sp);
+static void sppp_ipcp_open (struct sppp *sp);
+static int sppp_lcp_conf_parse_options (struct sppp *sp, struct lcp_header *h,
+	int len, u32 *magic);
+static void sppp_cp_timeout (unsigned long arg);
+static char *sppp_lcp_type_name (u8 type);
+static char *sppp_ipcp_type_name (u8 type);
+static void sppp_print_bytes (u8 *p, u16 len);
+
+static int debug;
+
+/* Flush global outgoing packet queue to dev_queue_xmit().
+ *
+ * dev_queue_xmit() must be called with interrupts enabled
+ * which means it can't be called with spinlocks held.
+ * If a packet needs to be sent while a spinlock is held,
+ * then put the packet into tx_queue, and call sppp_flush_xmit()
+ * after spinlock is released.
+ */
+static void sppp_flush_xmit(void)
+{
+	struct sk_buff *skb;
+	while ((skb = skb_dequeue(&tx_queue)) != NULL)
+		dev_queue_xmit(skb);
+}
+
+/*
+ *	Interface down stub
+ */	
+
+static void if_down(struct net_device *dev)
+{
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+
+	sp->pp_link_state=SPPP_LINK_DOWN;
+}
+
+/*
+ * Timeout routine activations.
+ */
+
+static void sppp_set_timeout(struct sppp *p,int s) 
+{
+	if (! (p->pp_flags & PP_TIMO)) 
+	{
+		init_timer(&p->pp_timer);
+		p->pp_timer.function=sppp_cp_timeout;
+		p->pp_timer.expires=jiffies+s*HZ;
+		p->pp_timer.data=(unsigned long)p;
+		p->pp_flags |= PP_TIMO;
+		add_timer(&p->pp_timer);
+	}
+}
+
+static void sppp_clear_timeout(struct sppp *p)
+{
+	if (p->pp_flags & PP_TIMO) 
+	{
+		del_timer(&p->pp_timer);
+		p->pp_flags &= ~PP_TIMO; 
+	}
+}
+
+/**
+ *	sppp_input -	receive and process a WAN PPP frame
+ *	@skb:	The buffer to process
+ *	@dev:	The device it arrived on
+ *
+ *	This can be called directly by cards that do not have
+ *	timing constraints but is normally called from the network layer
+ *	after interrupt servicing to process frames queued via netif_rx().
+ *
+ *	We process the options in the card. If the frame is destined for
+ *	the protocol stacks then it requeues the frame for the upper level
+ *	protocol. If it is a control from it is processed and discarded
+ *	here.
+ */
+ 
+void sppp_input (struct net_device *dev, struct sk_buff *skb)
+{
+	struct ppp_header *h;
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+	unsigned long flags;
+
+	skb->dev=dev;
+	skb->mac.raw=skb->data;
+
+	if (dev->flags & IFF_RUNNING)
+	{
+		/* Count received bytes, add FCS and one flag */
+		sp->ibytes+= skb->len + 3;
+		sp->ipkts++;
+	}
+
+	if (!pskb_may_pull(skb, PPP_HEADER_LEN)) {
+		/* Too small packet, drop it. */
+		if (sp->pp_flags & PP_DEBUG)
+			printk (KERN_DEBUG "%s: input packet is too small, %d bytes\n",
+				dev->name, skb->len);
+		kfree_skb(skb);
+		return;
+	}
+
+	/* Get PPP header. */
+	h = (struct ppp_header *)skb->data;
+	skb_pull(skb,sizeof(struct ppp_header));
+
+	spin_lock_irqsave(&sp->lock, flags);
+	
+	switch (h->address) {
+	default:        /* Invalid PPP packet. */
+		goto invalid;
+	case PPP_ALLSTATIONS:
+		if (h->control != PPP_UI)
+			goto invalid;
+		if (sp->pp_flags & PP_CISCO) {
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_WARNING "%s: PPP packet in Cisco mode <0x%x 0x%x 0x%x>\n",
+					dev->name,
+					h->address, h->control, ntohs (h->protocol));
+			goto drop;
+		}
+		switch (ntohs (h->protocol)) {
+		default:
+			if (sp->lcp.state == LCP_STATE_OPENED)
+				sppp_cp_send (sp, PPP_LCP, LCP_PROTO_REJ,
+					++sp->pp_seq, skb->len + 2,
+					&h->protocol);
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_WARNING "%s: invalid input protocol <0x%x 0x%x 0x%x>\n",
+					dev->name,
+					h->address, h->control, ntohs (h->protocol));
+			goto drop;
+		case PPP_LCP:
+			sppp_lcp_input (sp, skb);
+			goto drop;
+		case PPP_IPCP:
+			if (sp->lcp.state == LCP_STATE_OPENED)
+				sppp_ipcp_input (sp, skb);
+			else
+				printk(KERN_DEBUG "IPCP when still waiting LCP finish.\n");
+			goto drop;
+		case PPP_IP:
+			if (sp->ipcp.state == IPCP_STATE_OPENED) {
+				if(sp->pp_flags&PP_DEBUG)
+					printk(KERN_DEBUG "Yow an IP frame.\n");
+				skb->protocol=htons(ETH_P_IP);
+				netif_rx(skb);
+				dev->last_rx = jiffies;
+				goto done;
+			}
+			break;
+#ifdef IPX
+		case PPP_IPX:
+			/* IPX IPXCP not implemented yet */
+			if (sp->lcp.state == LCP_STATE_OPENED) {
+				skb->protocol=htons(ETH_P_IPX);
+				netif_rx(skb);
+				dev->last_rx = jiffies;
+				goto done;
+			}
+			break;
+#endif
+		}
+		break;
+	case CISCO_MULTICAST:
+	case CISCO_UNICAST:
+		/* Don't check the control field here (RFC 1547). */
+		if (! (sp->pp_flags & PP_CISCO)) {
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_WARNING "%s: Cisco packet in PPP mode <0x%x 0x%x 0x%x>\n",
+					dev->name,
+					h->address, h->control, ntohs (h->protocol));
+			goto drop;
+		}
+		switch (ntohs (h->protocol)) {
+		default:
+			goto invalid;
+		case CISCO_KEEPALIVE:
+			sppp_cisco_input (sp, skb);
+			goto drop;
+#ifdef CONFIG_INET
+		case ETH_P_IP:
+			skb->protocol=htons(ETH_P_IP);
+			netif_rx(skb);
+			dev->last_rx = jiffies;
+			goto done;
+#endif
+#ifdef CONFIG_IPX
+		case ETH_P_IPX:
+			skb->protocol=htons(ETH_P_IPX);
+			netif_rx(skb);
+			dev->last_rx = jiffies;
+			goto done;
+#endif
+		}
+		break;
+	}
+	goto drop;
+
+invalid:
+	if (sp->pp_flags & PP_DEBUG)
+		printk (KERN_WARNING "%s: invalid input packet <0x%x 0x%x 0x%x>\n",
+			dev->name, h->address, h->control, ntohs (h->protocol));
+drop:
+	kfree_skb(skb);
+done:
+	spin_unlock_irqrestore(&sp->lock, flags);
+	sppp_flush_xmit();
+	return;
+}
+
+EXPORT_SYMBOL(sppp_input);
+
+/*
+ *	Handle transmit packets.
+ */
+ 
+static int sppp_hard_header(struct sk_buff *skb, struct net_device *dev, __u16 type,
+		void *daddr, void *saddr, unsigned int len)
+{
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+	struct ppp_header *h;
+	skb_push(skb,sizeof(struct ppp_header));
+	h=(struct ppp_header *)skb->data;
+	if(sp->pp_flags&PP_CISCO)
+	{
+		h->address = CISCO_UNICAST;
+		h->control = 0;
+	}
+	else
+	{
+		h->address = PPP_ALLSTATIONS;
+		h->control = PPP_UI;
+	}
+	if(sp->pp_flags & PP_CISCO)
+	{
+		h->protocol = htons(type);
+	}
+	else switch(type)
+	{
+		case ETH_P_IP:
+			h->protocol = htons(PPP_IP);
+			break;
+		case ETH_P_IPX:
+			h->protocol = htons(PPP_IPX);
+			break;
+	}
+	return sizeof(struct ppp_header);
+}
+
+static int sppp_rebuild_header(struct sk_buff *skb)
+{
+	return 0;
+}
+
+/*
+ * Send keepalive packets, every 10 seconds.
+ */
+
+static void sppp_keepalive (unsigned long dummy)
+{
+	struct sppp *sp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&spppq_lock, flags);
+
+	for (sp=spppq; sp; sp=sp->pp_next) 
+	{
+		struct net_device *dev = sp->pp_if;
+
+		/* Keepalive mode disabled or channel down? */
+		if (! (sp->pp_flags & PP_KEEPALIVE) ||
+		    ! (dev->flags & IFF_UP))
+			continue;
+
+		spin_lock(&sp->lock);
+
+		/* No keepalive in PPP mode if LCP not opened yet. */
+		if (! (sp->pp_flags & PP_CISCO) &&
+		    sp->lcp.state != LCP_STATE_OPENED) {
+			spin_unlock(&sp->lock);
+			continue;
+		}
+
+		if (sp->pp_alivecnt == MAXALIVECNT) {
+			/* No keepalive packets got.  Stop the interface. */
+			printk (KERN_WARNING "%s: protocol down\n", dev->name);
+			if_down (dev);
+			if (! (sp->pp_flags & PP_CISCO)) {
+				/* Shut down the PPP link. */
+				sp->lcp.magic = jiffies;
+				sp->lcp.state = LCP_STATE_CLOSED;
+				sp->ipcp.state = IPCP_STATE_CLOSED;
+				sppp_clear_timeout (sp);
+				/* Initiate negotiation. */
+				sppp_lcp_open (sp);
+			}
+		}
+		if (sp->pp_alivecnt <= MAXALIVECNT)
+			++sp->pp_alivecnt;
+		if (sp->pp_flags & PP_CISCO)
+			sppp_cisco_send (sp, CISCO_KEEPALIVE_REQ, ++sp->pp_seq,
+				sp->pp_rseq);
+		else if (sp->lcp.state == LCP_STATE_OPENED) {
+			long nmagic = htonl (sp->lcp.magic);
+			sp->lcp.echoid = ++sp->pp_seq;
+			sppp_cp_send (sp, PPP_LCP, LCP_ECHO_REQ,
+				sp->lcp.echoid, 4, &nmagic);
+		}
+
+		spin_unlock(&sp->lock);
+	}
+	spin_unlock_irqrestore(&spppq_lock, flags);
+	sppp_flush_xmit();
+	sppp_keepalive_timer.expires=jiffies+10*HZ;
+	add_timer(&sppp_keepalive_timer);
+}
+
+/*
+ * Handle incoming PPP Link Control Protocol packets.
+ */
+ 
+static void sppp_lcp_input (struct sppp *sp, struct sk_buff *skb)
+{
+	struct lcp_header *h;
+	struct net_device *dev = sp->pp_if;
+	int len = skb->len;
+	u8 *p, opt[6];
+	u32 rmagic;
+
+	if (!pskb_may_pull(skb, sizeof(struct lcp_header))) {
+		if (sp->pp_flags & PP_DEBUG)
+			printk (KERN_WARNING "%s: invalid lcp packet length: %d bytes\n",
+				dev->name, len);
+		return;
+	}
+	h = (struct lcp_header *)skb->data;
+	skb_pull(skb,sizeof(struct lcp_header *));
+	
+	if (sp->pp_flags & PP_DEBUG) 
+	{
+		char state = '?';
+		switch (sp->lcp.state) {
+		case LCP_STATE_CLOSED:   state = 'C'; break;
+		case LCP_STATE_ACK_RCVD: state = 'R'; break;
+		case LCP_STATE_ACK_SENT: state = 'S'; break;
+		case LCP_STATE_OPENED:   state = 'O'; break;
+		}
+		printk (KERN_WARNING "%s: lcp input(%c): %d bytes <%s id=%xh len=%xh",
+			dev->name, state, len,
+			sppp_lcp_type_name (h->type), h->ident, ntohs (h->len));
+		if (len > 4)
+			sppp_print_bytes ((u8*) (h+1), len-4);
+		printk (">\n");
+	}
+	if (len > ntohs (h->len))
+		len = ntohs (h->len);
+	switch (h->type) {
+	default:
+		/* Unknown packet type -- send Code-Reject packet. */
+		sppp_cp_send (sp, PPP_LCP, LCP_CODE_REJ, ++sp->pp_seq,
+			skb->len, h);
+		break;
+	case LCP_CONF_REQ:
+		if (len < 4) {
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_DEBUG"%s: invalid lcp configure request packet length: %d bytes\n",
+					dev->name, len);
+			break;
+		}
+		if (len>4 && !sppp_lcp_conf_parse_options (sp, h, len, &rmagic))
+			goto badreq;
+		if (rmagic == sp->lcp.magic) {
+			/* Local and remote magics equal -- loopback? */
+			if (sp->pp_loopcnt >= MAXALIVECNT*5) {
+				printk (KERN_WARNING "%s: loopback\n",
+					dev->name);
+				sp->pp_loopcnt = 0;
+				if (dev->flags & IFF_UP) {
+					if_down (dev);
+				}
+			} else if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_DEBUG "%s: conf req: magic glitch\n",
+					dev->name);
+			++sp->pp_loopcnt;
+
+			/* MUST send Conf-Nack packet. */
+			rmagic = ~sp->lcp.magic;
+			opt[0] = LCP_OPT_MAGIC;
+			opt[1] = sizeof (opt);
+			opt[2] = rmagic >> 24;
+			opt[3] = rmagic >> 16;
+			opt[4] = rmagic >> 8;
+			opt[5] = rmagic;
+			sppp_cp_send (sp, PPP_LCP, LCP_CONF_NAK,
+				h->ident, sizeof (opt), &opt);
+badreq:
+			switch (sp->lcp.state) {
+			case LCP_STATE_OPENED:
+				/* Initiate renegotiation. */
+				sppp_lcp_open (sp);
+				/* fall through... */
+			case LCP_STATE_ACK_SENT:
+				/* Go to closed state. */
+				sp->lcp.state = LCP_STATE_CLOSED;
+				sp->ipcp.state = IPCP_STATE_CLOSED;
+			}
+			break;
+		}
+		/* Send Configure-Ack packet. */
+		sp->pp_loopcnt = 0;
+		if (sp->lcp.state != LCP_STATE_OPENED) {
+			sppp_cp_send (sp, PPP_LCP, LCP_CONF_ACK,
+					h->ident, len-4, h+1);
+		}
+		/* Change the state. */
+		switch (sp->lcp.state) {
+		case LCP_STATE_CLOSED:
+			sp->lcp.state = LCP_STATE_ACK_SENT;
+			break;
+		case LCP_STATE_ACK_RCVD:
+			sp->lcp.state = LCP_STATE_OPENED;
+			sppp_ipcp_open (sp);
+			break;
+		case LCP_STATE_OPENED:
+			/* Remote magic changed -- close session. */
+			sp->lcp.state = LCP_STATE_CLOSED;
+			sp->ipcp.state = IPCP_STATE_CLOSED;
+			/* Initiate renegotiation. */
+			sppp_lcp_open (sp);
+			/* Send ACK after our REQ in attempt to break loop */
+			sppp_cp_send (sp, PPP_LCP, LCP_CONF_ACK,
+					h->ident, len-4, h+1);
+			sp->lcp.state = LCP_STATE_ACK_SENT;
+			break;
+		}
+		break;
+	case LCP_CONF_ACK:
+		if (h->ident != sp->lcp.confid)
+			break;
+		sppp_clear_timeout (sp);
+		if ((sp->pp_link_state != SPPP_LINK_UP) &&
+		    (dev->flags & IFF_UP)) {
+			/* Coming out of loopback mode. */
+			sp->pp_link_state=SPPP_LINK_UP;
+			printk (KERN_INFO "%s: protocol up\n", dev->name);
+		}
+		switch (sp->lcp.state) {
+		case LCP_STATE_CLOSED:
+			sp->lcp.state = LCP_STATE_ACK_RCVD;
+			sppp_set_timeout (sp, 5);
+			break;
+		case LCP_STATE_ACK_SENT:
+			sp->lcp.state = LCP_STATE_OPENED;
+			sppp_ipcp_open (sp);
+			break;
+		}
+		break;
+	case LCP_CONF_NAK:
+		if (h->ident != sp->lcp.confid)
+			break;
+		p = (u8*) (h+1);
+		if (len>=10 && p[0] == LCP_OPT_MAGIC && p[1] >= 4) {
+			rmagic = (u32)p[2] << 24 |
+				(u32)p[3] << 16 | p[4] << 8 | p[5];
+			if (rmagic == ~sp->lcp.magic) {
+				int newmagic;
+				if (sp->pp_flags & PP_DEBUG)
+					printk (KERN_DEBUG "%s: conf nak: magic glitch\n",
+						dev->name);
+				get_random_bytes(&newmagic, sizeof(newmagic));
+				sp->lcp.magic += newmagic;
+			} else
+				sp->lcp.magic = rmagic;
+			}
+		if (sp->lcp.state != LCP_STATE_ACK_SENT) {
+			/* Go to closed state. */
+			sp->lcp.state = LCP_STATE_CLOSED;
+			sp->ipcp.state = IPCP_STATE_CLOSED;
+		}
+		/* The link will be renegotiated after timeout,
+		 * to avoid endless req-nack loop. */
+		sppp_clear_timeout (sp);
+		sppp_set_timeout (sp, 2);
+		break;
+	case LCP_CONF_REJ:
+		if (h->ident != sp->lcp.confid)
+			break;
+		sppp_clear_timeout (sp);
+		/* Initiate renegotiation. */
+		sppp_lcp_open (sp);
+		if (sp->lcp.state != LCP_STATE_ACK_SENT) {
+			/* Go to closed state. */
+			sp->lcp.state = LCP_STATE_CLOSED;
+			sp->ipcp.state = IPCP_STATE_CLOSED;
+		}
+		break;
+	case LCP_TERM_REQ:
+		sppp_clear_timeout (sp);
+		/* Send Terminate-Ack packet. */
+		sppp_cp_send (sp, PPP_LCP, LCP_TERM_ACK, h->ident, 0, NULL);
+		/* Go to closed state. */
+		sp->lcp.state = LCP_STATE_CLOSED;
+		sp->ipcp.state = IPCP_STATE_CLOSED;
+		/* Initiate renegotiation. */
+		sppp_lcp_open (sp);
+		break;
+	case LCP_TERM_ACK:
+	case LCP_CODE_REJ:
+	case LCP_PROTO_REJ:
+		/* Ignore for now. */
+		break;
+	case LCP_DISC_REQ:
+		/* Discard the packet. */
+		break;
+	case LCP_ECHO_REQ:
+		if (sp->lcp.state != LCP_STATE_OPENED)
+			break;
+		if (len < 8) {
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_WARNING "%s: invalid lcp echo request packet length: %d bytes\n",
+					dev->name, len);
+			break;
+		}
+		if (ntohl (*(long*)(h+1)) == sp->lcp.magic) {
+			/* Line loopback mode detected. */
+			printk (KERN_WARNING "%s: loopback\n", dev->name);
+			if_down (dev);
+
+			/* Shut down the PPP link. */
+			sp->lcp.state = LCP_STATE_CLOSED;
+			sp->ipcp.state = IPCP_STATE_CLOSED;
+			sppp_clear_timeout (sp);
+			/* Initiate negotiation. */
+			sppp_lcp_open (sp);
+			break;
+		}
+		*(long*)(h+1) = htonl (sp->lcp.magic);
+		sppp_cp_send (sp, PPP_LCP, LCP_ECHO_REPLY, h->ident, len-4, h+1);
+		break;
+	case LCP_ECHO_REPLY:
+		if (h->ident != sp->lcp.echoid)
+			break;
+		if (len < 8) {
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_WARNING "%s: invalid lcp echo reply packet length: %d bytes\n",
+					dev->name, len);
+			break;
+		}
+		if (ntohl (*(long*)(h+1)) != sp->lcp.magic)
+		sp->pp_alivecnt = 0;
+		break;
+	}
+}
+
+/*
+ * Handle incoming Cisco keepalive protocol packets.
+ */
+
+static void sppp_cisco_input (struct sppp *sp, struct sk_buff *skb)
+{
+	struct cisco_packet *h;
+	struct net_device *dev = sp->pp_if;
+
+	if (!pskb_may_pull(skb, sizeof(struct cisco_packet))
+	    || (skb->len != CISCO_PACKET_LEN
+		&& skb->len != CISCO_BIG_PACKET_LEN)) {
+		if (sp->pp_flags & PP_DEBUG)
+			printk (KERN_WARNING "%s: invalid cisco packet length: %d bytes\n",
+				dev->name,  skb->len);
+		return;
+	}
+	h = (struct cisco_packet *)skb->data;
+	skb_pull(skb, sizeof(struct cisco_packet*));
+	if (sp->pp_flags & PP_DEBUG)
+		printk (KERN_WARNING "%s: cisco input: %d bytes <%xh %xh %xh %xh %xh-%xh>\n",
+			dev->name,  skb->len,
+			ntohl (h->type), h->par1, h->par2, h->rel,
+			h->time0, h->time1);
+	switch (ntohl (h->type)) {
+	default:
+		if (sp->pp_flags & PP_DEBUG)
+			printk (KERN_WARNING "%s: unknown cisco packet type: 0x%x\n",
+				dev->name,  ntohl (h->type));
+		break;
+	case CISCO_ADDR_REPLY:
+		/* Reply on address request, ignore */
+		break;
+	case CISCO_KEEPALIVE_REQ:
+		sp->pp_alivecnt = 0;
+		sp->pp_rseq = ntohl (h->par1);
+		if (sp->pp_seq == sp->pp_rseq) {
+			/* Local and remote sequence numbers are equal.
+			 * Probably, the line is in loopback mode. */
+			int newseq;
+			if (sp->pp_loopcnt >= MAXALIVECNT) {
+				printk (KERN_WARNING "%s: loopback\n",
+					dev->name);
+				sp->pp_loopcnt = 0;
+				if (dev->flags & IFF_UP) {
+					if_down (dev);
+				}
+			}
+			++sp->pp_loopcnt;
+
+			/* Generate new local sequence number */
+			get_random_bytes(&newseq, sizeof(newseq));
+			sp->pp_seq ^= newseq;
+			break;
+		}
+		sp->pp_loopcnt = 0;
+		if (sp->pp_link_state==SPPP_LINK_DOWN &&
+		    (dev->flags & IFF_UP)) {
+			sp->pp_link_state=SPPP_LINK_UP;
+			printk (KERN_INFO "%s: protocol up\n", dev->name);
+		}
+		break;
+	case CISCO_ADDR_REQ:
+		/* Stolen from net/ipv4/devinet.c -- SIOCGIFADDR ioctl */
+		{
+		struct in_device *in_dev;
+		struct in_ifaddr *ifa;
+		u32 addr = 0, mask = ~0; /* FIXME: is the mask correct? */
+#ifdef CONFIG_INET
+		rcu_read_lock();
+		if ((in_dev = __in_dev_get(dev)) != NULL)
+		{
+			for (ifa=in_dev->ifa_list; ifa != NULL;
+				ifa=ifa->ifa_next) {
+				if (strcmp(dev->name, ifa->ifa_label) == 0) 
+				{
+					addr = ifa->ifa_local;
+					mask = ifa->ifa_mask;
+					break;
+				}
+			}
+		}
+		rcu_read_unlock();
+#endif		
+		/* I hope both addr and mask are in the net order */
+		sppp_cisco_send (sp, CISCO_ADDR_REPLY, addr, mask);
+		break;
+		}
+	}
+}
+
+
+/*
+ * Send PPP LCP packet.
+ */
+
+static void sppp_cp_send (struct sppp *sp, u16 proto, u8 type,
+	u8 ident, u16 len, void *data)
+{
+	struct ppp_header *h;
+	struct lcp_header *lh;
+	struct sk_buff *skb;
+	struct net_device *dev = sp->pp_if;
+
+	skb=alloc_skb(dev->hard_header_len+PPP_HEADER_LEN+LCP_HEADER_LEN+len,
+		GFP_ATOMIC);
+	if (skb==NULL)
+		return;
+
+	skb_reserve(skb,dev->hard_header_len);
+	
+	h = (struct ppp_header *)skb_put(skb, sizeof(struct ppp_header));
+	h->address = PPP_ALLSTATIONS;        /* broadcast address */
+	h->control = PPP_UI;                 /* Unnumbered Info */
+	h->protocol = htons (proto);         /* Link Control Protocol */
+
+	lh = (struct lcp_header *)skb_put(skb, sizeof(struct lcp_header));
+	lh->type = type;
+	lh->ident = ident;
+	lh->len = htons (LCP_HEADER_LEN + len);
+
+	if (len)
+		memcpy(skb_put(skb,len),data, len);
+
+	if (sp->pp_flags & PP_DEBUG) {
+		printk (KERN_WARNING "%s: %s output <%s id=%xh len=%xh",
+			dev->name, 
+			proto==PPP_LCP ? "lcp" : "ipcp",
+			proto==PPP_LCP ? sppp_lcp_type_name (lh->type) :
+			sppp_ipcp_type_name (lh->type), lh->ident,
+			ntohs (lh->len));
+		if (len)
+			sppp_print_bytes ((u8*) (lh+1), len);
+		printk (">\n");
+	}
+	sp->obytes += skb->len;
+	/* Control is high priority so it doesn't get queued behind data */
+	skb->priority=TC_PRIO_CONTROL;
+	skb->dev = dev;
+	skb_queue_tail(&tx_queue, skb);
+}
+
+/*
+ * Send Cisco keepalive packet.
+ */
+
+static void sppp_cisco_send (struct sppp *sp, int type, long par1, long par2)
+{
+	struct ppp_header *h;
+	struct cisco_packet *ch;
+	struct sk_buff *skb;
+	struct net_device *dev = sp->pp_if;
+	u32 t = jiffies * 1000/HZ;
+
+	skb=alloc_skb(dev->hard_header_len+PPP_HEADER_LEN+CISCO_PACKET_LEN,
+		GFP_ATOMIC);
+
+	if(skb==NULL)
+		return;
+		
+	skb_reserve(skb, dev->hard_header_len);
+	h = (struct ppp_header *)skb_put (skb, sizeof(struct ppp_header));
+	h->address = CISCO_MULTICAST;
+	h->control = 0;
+	h->protocol = htons (CISCO_KEEPALIVE);
+
+	ch = (struct cisco_packet*)skb_put(skb, CISCO_PACKET_LEN);
+	ch->type = htonl (type);
+	ch->par1 = htonl (par1);
+	ch->par2 = htonl (par2);
+	ch->rel = -1;
+	ch->time0 = htons ((u16) (t >> 16));
+	ch->time1 = htons ((u16) t);
+
+	if (sp->pp_flags & PP_DEBUG)
+		printk (KERN_WARNING "%s: cisco output: <%xh %xh %xh %xh %xh-%xh>\n",
+			dev->name,  ntohl (ch->type), ch->par1,
+			ch->par2, ch->rel, ch->time0, ch->time1);
+	sp->obytes += skb->len;
+	skb->priority=TC_PRIO_CONTROL;
+	skb->dev = dev;
+	skb_queue_tail(&tx_queue, skb);
+}
+
+/**
+ *	sppp_close - close down a synchronous PPP or Cisco HDLC link
+ *	@dev: The network device to drop the link of
+ *
+ *	This drops the logical interface to the channel. It is not
+ *	done politely as we assume we will also be dropping DTR. Any
+ *	timeouts are killed.
+ */
+
+int sppp_close (struct net_device *dev)
+{
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&sp->lock, flags);
+	sp->pp_link_state = SPPP_LINK_DOWN;
+	sp->lcp.state = LCP_STATE_CLOSED;
+	sp->ipcp.state = IPCP_STATE_CLOSED;
+	sppp_clear_timeout (sp);
+	spin_unlock_irqrestore(&sp->lock, flags);
+
+	return 0;
+}
+
+EXPORT_SYMBOL(sppp_close);
+
+/**
+ *	sppp_open - open a synchronous PPP or Cisco HDLC link
+ *	@dev:	Network device to activate
+ *	
+ *	Close down any existing synchronous session and commence
+ *	from scratch. In the PPP case this means negotiating LCP/IPCP
+ *	and friends, while for Cisco HDLC we simply need to start sending
+ *	keepalives
+ */
+
+int sppp_open (struct net_device *dev)
+{
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+	unsigned long flags;
+
+	sppp_close(dev);
+
+	spin_lock_irqsave(&sp->lock, flags);
+	if (!(sp->pp_flags & PP_CISCO)) {
+		sppp_lcp_open (sp);
+	}
+	sp->pp_link_state = SPPP_LINK_DOWN;
+	spin_unlock_irqrestore(&sp->lock, flags);
+	sppp_flush_xmit();
+
+	return 0;
+}
+
+EXPORT_SYMBOL(sppp_open);
+
+/**
+ *	sppp_reopen - notify of physical link loss
+ *	@dev: Device that lost the link
+ *
+ *	This function informs the synchronous protocol code that
+ *	the underlying link died (for example a carrier drop on X.21)
+ *
+ *	We increment the magic numbers to ensure that if the other end
+ *	failed to notice we will correctly start a new session. It happens
+ *	do to the nature of telco circuits is that you can lose carrier on
+ *	one endonly.
+ *
+ *	Having done this we go back to negotiating. This function may
+ *	be called from an interrupt context.
+ */
+ 
+int sppp_reopen (struct net_device *dev)
+{
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+	unsigned long flags;
+
+	sppp_close(dev);
+
+	spin_lock_irqsave(&sp->lock, flags);
+	if (!(sp->pp_flags & PP_CISCO))
+	{
+		sp->lcp.magic = jiffies;
+		++sp->pp_seq;
+		sp->lcp.state = LCP_STATE_CLOSED;
+		sp->ipcp.state = IPCP_STATE_CLOSED;
+		/* Give it a moment for the line to settle then go */
+		sppp_set_timeout (sp, 1);
+	} 
+	sp->pp_link_state=SPPP_LINK_DOWN;
+	spin_unlock_irqrestore(&sp->lock, flags);
+
+	return 0;
+}
+
+EXPORT_SYMBOL(sppp_reopen);
+
+/**
+ *	sppp_change_mtu - Change the link MTU
+ *	@dev:	Device to change MTU on
+ *	@new_mtu: New MTU
+ *
+ *	Change the MTU on the link. This can only be called with
+ *	the link down. It returns an error if the link is up or
+ *	the mtu is out of range.
+ */
+ 
+int sppp_change_mtu(struct net_device *dev, int new_mtu)
+{
+	if(new_mtu<128||new_mtu>PPP_MTU||(dev->flags&IFF_UP))
+		return -EINVAL;
+	dev->mtu=new_mtu;
+	return 0;
+}
+
+EXPORT_SYMBOL(sppp_change_mtu);
+
+/**
+ *	sppp_do_ioctl - Ioctl handler for ppp/hdlc
+ *	@dev: Device subject to ioctl
+ *	@ifr: Interface request block from the user
+ *	@cmd: Command that is being issued
+ *	
+ *	This function handles the ioctls that may be issued by the user
+ *	to control the settings of a PPP/HDLC link. It does both busy
+ *	and security checks. This function is intended to be wrapped by
+ *	callers who wish to add additional ioctl calls of their own.
+ */
+ 
+int sppp_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	struct sppp *sp = (struct sppp *)sppp_of(dev);
+
+	if(dev->flags&IFF_UP)
+		return -EBUSY;
+		
+	if(!capable(CAP_NET_ADMIN))
+		return -EPERM;
+	
+	switch(cmd)
+	{
+		case SPPPIOCCISCO:
+			sp->pp_flags|=PP_CISCO;
+			dev->type = ARPHRD_HDLC;
+			break;
+		case SPPPIOCPPP:
+			sp->pp_flags&=~PP_CISCO;
+			dev->type = ARPHRD_PPP;
+			break;
+		case SPPPIOCDEBUG:
+			sp->pp_flags&=~PP_DEBUG;
+			if(ifr->ifr_flags)
+				sp->pp_flags|=PP_DEBUG;
+			break;
+		case SPPPIOCGFLAGS:
+			if(copy_to_user(ifr->ifr_data, &sp->pp_flags, sizeof(sp->pp_flags)))
+				return -EFAULT;
+			break;
+		case SPPPIOCSFLAGS:
+			if(copy_from_user(&sp->pp_flags, ifr->ifr_data, sizeof(sp->pp_flags)))
+				return -EFAULT;
+			break;
+		default:
+			return -EINVAL;
+	}
+	return 0;
+}
+
+EXPORT_SYMBOL(sppp_do_ioctl);
+
+/**
+ *	sppp_attach - attach synchronous PPP/HDLC to a device
+ *	@pd:	PPP device to initialise
+ *
+ *	This initialises the PPP/HDLC support on an interface. At the
+ *	time of calling the dev element must point to the network device
+ *	that this interface is attached to. The interface should not yet
+ *	be registered. 
+ */
+ 
+void sppp_attach(struct ppp_device *pd)
+{
+	struct net_device *dev = pd->dev;
+	struct sppp *sp = &pd->sppp;
+	unsigned long flags;
+
+	/* Make sure embedding is safe for sppp_of */
+	BUG_ON(sppp_of(dev) != sp);
+
+	spin_lock_irqsave(&spppq_lock, flags);
+	/* Initialize keepalive handler. */
+	if (! spppq)
+	{
+		init_timer(&sppp_keepalive_timer);
+		sppp_keepalive_timer.expires=jiffies+10*HZ;
+		sppp_keepalive_timer.function=sppp_keepalive;
+		add_timer(&sppp_keepalive_timer);
+	}
+	/* Insert new entry into the keepalive list. */
+	sp->pp_next = spppq;
+	spppq = sp;
+	spin_unlock_irqrestore(&spppq_lock, flags);
+
+	sp->pp_loopcnt = 0;
+	sp->pp_alivecnt = 0;
+	sp->pp_seq = 0;
+	sp->pp_rseq = 0;
+	sp->pp_flags = PP_KEEPALIVE|PP_CISCO|debug;/*PP_DEBUG;*/
+	sp->lcp.magic = 0;
+	sp->lcp.state = LCP_STATE_CLOSED;
+	sp->ipcp.state = IPCP_STATE_CLOSED;
+	sp->pp_if = dev;
+	spin_lock_init(&sp->lock);
+	
+	/* 
+	 *	Device specific setup. All but interrupt handler and
+	 *	hard_start_xmit.
+	 */
+	 
+	dev->hard_header = sppp_hard_header;
+	dev->rebuild_header = sppp_rebuild_header;
+	dev->tx_queue_len = 10;
+	dev->type = ARPHRD_HDLC;
+	dev->addr_len = 0;
+	dev->hard_header_len = sizeof(struct ppp_header);
+	dev->mtu = PPP_MTU;
+	/*
+	 *	These 4 are callers but MUST also call sppp_ functions
+	 */
+	dev->do_ioctl = sppp_do_ioctl;
+#if 0
+	dev->get_stats = NULL;		/* Let the driver override these */
+	dev->open = sppp_open;
+	dev->stop = sppp_close;
+#endif	
+	dev->change_mtu = sppp_change_mtu;
+	dev->hard_header_cache = NULL;
+	dev->header_cache_update = NULL;
+	dev->flags = IFF_MULTICAST|IFF_POINTOPOINT|IFF_NOARP;
+}
+
+EXPORT_SYMBOL(sppp_attach);
+
+/**
+ *	sppp_detach - release PPP resources from a device
+ *	@dev:	Network device to release
+ *
+ *	Stop and free up any PPP/HDLC resources used by this
+ *	interface. This must be called before the device is
+ *	freed.
+ */
+ 
+void sppp_detach (struct net_device *dev)
+{
+	struct sppp **q, *p, *sp = (struct sppp *)sppp_of(dev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&spppq_lock, flags);
+	/* Remove the entry from the keepalive list. */
+	for (q = &spppq; (p = *q); q = &p->pp_next)
+		if (p == sp) {
+			*q = p->pp_next;
+			break;
+		}
+
+	/* Stop keepalive handler. */
+	if (! spppq)
+		del_timer(&sppp_keepalive_timer);
+	sppp_clear_timeout (sp);
+	spin_unlock_irqrestore(&spppq_lock, flags);
+}
+
+EXPORT_SYMBOL(sppp_detach);
+
+/*
+ * Analyze the LCP Configure-Request options list
+ * for the presence of unknown options.
+ * If the request contains unknown options, build and
+ * send Configure-reject packet, containing only unknown options.
+ */
+static int
+sppp_lcp_conf_parse_options (struct sppp *sp, struct lcp_header *h,
+	int len, u32 *magic)
+{
+	u8 *buf, *r, *p;
+	int rlen;
+
+	len -= 4;
+	buf = r = kmalloc (len, GFP_ATOMIC);
+	if (! buf)
+		return (0);
+
+	p = (void*) (h+1);
+	for (rlen=0; len>1 && p[1]; len-=p[1], p+=p[1]) {
+		switch (*p) {
+		case LCP_OPT_MAGIC:
+			/* Magic number -- extract. */
+			if (len >= 6 && p[1] == 6) {
+				*magic = (u32)p[2] << 24 |
+					(u32)p[3] << 16 | p[4] << 8 | p[5];
+				continue;
+			}
+			break;
+		case LCP_OPT_ASYNC_MAP:
+			/* Async control character map -- check to be zero. */
+			if (len >= 6 && p[1] == 6 && ! p[2] && ! p[3] &&
+			    ! p[4] && ! p[5])
+				continue;
+			break;
+		case LCP_OPT_MRU:
+			/* Maximum receive unit -- always OK. */
+			continue;
+		default:
+			/* Others not supported. */
+			break;
+		}
+		/* Add the option to rejected list. */
+		memcpy(r, p, p[1]);
+		r += p[1];
+		rlen += p[1];
+	}
+	if (rlen)
+		sppp_cp_send (sp, PPP_LCP, LCP_CONF_REJ, h->ident, rlen, buf);
+	kfree(buf);
+	return (rlen == 0);
+}
+
+static void sppp_ipcp_input (struct sppp *sp, struct sk_buff *skb)
+{
+	struct lcp_header *h;
+	struct net_device *dev = sp->pp_if;
+	int len = skb->len;
+
+	if (!pskb_may_pull(skb, sizeof(struct lcp_header))) {
+		if (sp->pp_flags & PP_DEBUG)
+			printk (KERN_WARNING "%s: invalid ipcp packet length: %d bytes\n",
+				dev->name,  len);
+		return;
+	}
+	h = (struct lcp_header *)skb->data;
+	skb_pull(skb,sizeof(struct lcp_header));
+	if (sp->pp_flags & PP_DEBUG) {
+		printk (KERN_WARNING "%s: ipcp input: %d bytes <%s id=%xh len=%xh",
+			dev->name,  len,
+			sppp_ipcp_type_name (h->type), h->ident, ntohs (h->len));
+		if (len > 4)
+			sppp_print_bytes ((u8*) (h+1), len-4);
+		printk (">\n");
+	}
+	if (len > ntohs (h->len))
+		len = ntohs (h->len);
+	switch (h->type) {
+	default:
+		/* Unknown packet type -- send Code-Reject packet. */
+		sppp_cp_send (sp, PPP_IPCP, IPCP_CODE_REJ, ++sp->pp_seq, len, h);
+		break;
+	case IPCP_CONF_REQ:
+		if (len < 4) {
+			if (sp->pp_flags & PP_DEBUG)
+				printk (KERN_WARNING "%s: invalid ipcp configure request packet length: %d bytes\n",
+					dev->name, len);
+			return;
+		}
+		if (len > 4) {
+			sppp_cp_send (sp, PPP_IPCP, LCP_CONF_REJ, h->ident,
+				len-4, h+1);
+
+			switch (sp->ipcp.state) {
+			case IPCP_STATE_OPENED:
+				/* Initiate renegotiation. */
+				sppp_ipcp_open (sp);
+				/* fall through... */
+			case IPCP_STATE_ACK_SENT:
+				/* Go to closed state. */
+				sp->ipcp.state = IPCP_STATE_CLOSED;
+			}
+		} else {
+			/* Send Configure-Ack packet. */
+			sppp_cp_send (sp, PPP_IPCP, IPCP_CONF_ACK, h->ident,
+				0, NULL);
+			/* Change the state. */
+			if (sp->ipcp.state == IPCP_STATE_ACK_RCVD)
+				sp->ipcp.state = IPCP_STATE_OPENED;
+			else
+				sp->ipcp.state = IPCP_STATE_ACK_SENT;
+		}
+		break;
+	case IPCP_CONF_ACK:
+		if (h->ident != sp->ipcp.confid)
+			break;
+		sppp_clear_timeout (sp);
+		switch (sp->ipcp.state) {
+		case IPCP_STATE_CLOSED:
+			sp->ipcp.state = IPCP_STATE_ACK_RCVD;
+			sppp_set_timeout (sp, 5);
+			break;
+		case IPCP_STATE_ACK_SENT:
+			sp->ipcp.state = IPCP_STATE_OPENED;
+			break;
+		}
+		break;
+	case IPCP_CONF_NAK:
+	case IPCP_CONF_REJ:
+		if (h->ident != sp->ipcp.confid)
+			break;
+		sppp_clear_timeout (sp);
+			/* Initiate renegotiation. */
+		sppp_ipcp_open (sp);
+		if (sp->ipcp.state != IPCP_STATE_ACK_SENT)
+			/* Go to closed state. */
+			sp->ipcp.state = IPCP_STATE_CLOSED;
+		break;
+	case IPCP_TERM_REQ:
+		/* Send Terminate-Ack packet. */
+		sppp_cp_send (sp, PPP_IPCP, IPCP_TERM_ACK, h->ident, 0, NULL);
+		/* Go to closed state. */
+		sp->ipcp.state = IPCP_STATE_CLOSED;
+		/* Initiate renegotiation. */
+		sppp_ipcp_open (sp);
+		break;
+	case IPCP_TERM_ACK:
+		/* Ignore for now. */
+	case IPCP_CODE_REJ:
+		/* Ignore for now. */
+		break;
+	}
+}
+
+static void sppp_lcp_open (struct sppp *sp)
+{
+	char opt[6];
+
+	if (! sp->lcp.magic)
+		sp->lcp.magic = jiffies;
+	opt[0] = LCP_OPT_MAGIC;
+	opt[1] = sizeof (opt);
+	opt[2] = sp->lcp.magic >> 24;
+	opt[3] = sp->lcp.magic >> 16;
+	opt[4] = sp->lcp.magic >> 8;
+	opt[5] = sp->lcp.magic;
+	sp->lcp.confid = ++sp->pp_seq;
+	sppp_cp_send (sp, PPP_LCP, LCP_CONF_REQ, sp->lcp.confid,
+		sizeof (opt), &opt);
+	sppp_set_timeout (sp, 2);
+}
+
+static void sppp_ipcp_open (struct sppp *sp)
+{
+	sp->ipcp.confid = ++sp->pp_seq;
+	sppp_cp_send (sp, PPP_IPCP, IPCP_CONF_REQ, sp->ipcp.confid, 0, NULL);
+	sppp_set_timeout (sp, 2);
+}
+
+/*
+ * Process PPP control protocol timeouts.
+ */
+ 
+static void sppp_cp_timeout (unsigned long arg)
+{
+	struct sppp *sp = (struct sppp*) arg;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sp->lock, flags);
+
+	sp->pp_flags &= ~PP_TIMO;
+	if (! (sp->pp_if->flags & IFF_UP) || (sp->pp_flags & PP_CISCO)) {
+		spin_unlock_irqrestore(&sp->lock, flags);
+		return;
+	}
+	switch (sp->lcp.state) {
+	case LCP_STATE_CLOSED:
+		/* No ACK for Configure-Request, retry. */
+		sppp_lcp_open (sp);
+		break;
+	case LCP_STATE_ACK_RCVD:
+		/* ACK got, but no Configure-Request for peer, retry. */
+		sppp_lcp_open (sp);
+		sp->lcp.state = LCP_STATE_CLOSED;
+		break;
+	case LCP_STATE_ACK_SENT:
+		/* ACK sent but no ACK for Configure-Request, retry. */
+		sppp_lcp_open (sp);
+		break;
+	case LCP_STATE_OPENED:
+		/* LCP is already OK, try IPCP. */
+		switch (sp->ipcp.state) {
+		case IPCP_STATE_CLOSED:
+			/* No ACK for Configure-Request, retry. */
+			sppp_ipcp_open (sp);
+			break;
+		case IPCP_STATE_ACK_RCVD:
+			/* ACK got, but no Configure-Request for peer, retry. */
+			sppp_ipcp_open (sp);
+			sp->ipcp.state = IPCP_STATE_CLOSED;
+			break;
+		case IPCP_STATE_ACK_SENT:
+			/* ACK sent but no ACK for Configure-Request, retry. */
+			sppp_ipcp_open (sp);
+			break;
+		case IPCP_STATE_OPENED:
+			/* IPCP is OK. */
+			break;
+		}
+		break;
+	}
+	spin_unlock_irqrestore(&sp->lock, flags);
+	sppp_flush_xmit();
+}
+
+static char *sppp_lcp_type_name (u8 type)
+{
+	static char buf [8];
+	switch (type) {
+	case LCP_CONF_REQ:   return ("conf-req");
+	case LCP_CONF_ACK:   return ("conf-ack");
+	case LCP_CONF_NAK:   return ("conf-nack");
+	case LCP_CONF_REJ:   return ("conf-rej");
+	case LCP_TERM_REQ:   return ("term-req");
+	case LCP_TERM_ACK:   return ("term-ack");
+	case LCP_CODE_REJ:   return ("code-rej");
+	case LCP_PROTO_REJ:  return ("proto-rej");
+	case LCP_ECHO_REQ:   return ("echo-req");
+	case LCP_ECHO_REPLY: return ("echo-reply");
+	case LCP_DISC_REQ:   return ("discard-req");
+	}
+	sprintf (buf, "%xh", type);
+	return (buf);
+}
+
+static char *sppp_ipcp_type_name (u8 type)
+{
+	static char buf [8];
+	switch (type) {
+	case IPCP_CONF_REQ:   return ("conf-req");
+	case IPCP_CONF_ACK:   return ("conf-ack");
+	case IPCP_CONF_NAK:   return ("conf-nack");
+	case IPCP_CONF_REJ:   return ("conf-rej");
+	case IPCP_TERM_REQ:   return ("term-req");
+	case IPCP_TERM_ACK:   return ("term-ack");
+	case IPCP_CODE_REJ:   return ("code-rej");
+	}
+	sprintf (buf, "%xh", type);
+	return (buf);
+}
+
+static void sppp_print_bytes (u_char *p, u16 len)
+{
+	printk (" %x", *p++);
+	while (--len > 0)
+		printk ("-%x", *p++);
+}
+
+/**
+ *	sppp_rcv -	receive and process a WAN PPP frame
+ *	@skb:	The buffer to process
+ *	@dev:	The device it arrived on
+ *	@p: Unused
+ *
+ *	Protocol glue. This drives the deferred processing mode the poorer
+ *	cards use. This can be called directly by cards that do not have
+ *	timing constraints but is normally called from the network layer
+ *	after interrupt servicing to process frames queued via netif_rx.
+ */
+
+static int sppp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *p)
+{
+	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
+		return NET_RX_DROP;
+	sppp_input(dev,skb);
+	return 0;
+}
+
+struct packet_type sppp_packet_type = {
+	.type	= __constant_htons(ETH_P_WAN_PPP),
+	.func	= sppp_rcv,
+};
+
+static char banner[] __initdata = 
+	KERN_INFO "Cronyx Ltd, Synchronous PPP and CISCO HDLC (c) 1994\n"
+	KERN_INFO "Linux port (c) 1998 Building Number Three Ltd & "
+		  "Jan \"Yenya\" Kasprzak.\n";
+
+static int __init sync_ppp_init(void)
+{
+	if(debug)
+		debug=PP_DEBUG;
+	printk(banner);
+	skb_queue_head_init(&tx_queue);
+	dev_add_pack(&sppp_packet_type);
+	return 0;
+}
+
+
+static void __exit sync_ppp_cleanup(void)
+{
+	dev_remove_pack(&sppp_packet_type);
+}
+
+module_init(sync_ppp_init);
+module_exit(sync_ppp_cleanup);
+module_param(debug, int, 0);
+MODULE_LICENSE("GPL");
+