/*
 * channel.cc - Low-level channel functions interacting between the device
 *             and link layers
 * Copyright (C) 1997-2000 SpellCaster Telecommunications Inc.
 * $Id: channel.cc,v 1.4 2004/07/30 02:47:51 bcrl Exp $
 * Released under the GNU Public License. See LICENSE file for details.
 */

#include <errno.h>

#include "kernel.h"
#include "link.h"
#include "d_aps_if.h"
#include "md5.h"
#include "iface.h"
#include "bpppoe.h"

extern int RegisterChannel(channel_t *);
extern void UnregisterChannel(channel_t *);
extern void ChannelUp(channel_t *);
extern void ChannelOpen(channel_t *);
extern void ChannelDown(channel_t *);
extern void ChannelConnectComplete(channel_t *, int);
extern void DialGotConfig(void *, OptionSet_t *);
extern void DialReport(DialResponse_t *);

extern policy_t g_policy;

/*
 * Number of registered channels
 */
static unsigned short nr_channels[2] = {0,250};

#define MAX_KEYS	16

static u8	keys[MAX_KEYS][16];
static int	numKeys = 0;

u16 next_ldisc = 1;

extern "C" {
	void MD5Init(MD5_CTX *);
	void MD5Update(MD5_CTX *, unsigned char *, unsigned int);
	void MD5Final(MD5_CTX *);
};

/*
 * the key is a 32 byte entity, the first 16 bytes of which are 'public'
 * data, and the last 16 bytes of which are the md5 sum of the public portion
 * with the secret below.
 * The first byte of the key is the number of licenses it is valid for.  The
 * rest are completely irrelevant.
 */
int RegisterMoreChannels(u8 *key)
{
	MD5_CTX md5;
	MD5Init(&md5);
	MD5Update(&md5, key, 16);
	MD5Update(&md5, (unsigned char *)
		"\x16\xb6\x80\xcb\x1e\xcc\x01\xbe\x32\x1a\x8c\x9d\xaf\x92\x22\x0d"
		"\x74\xd0\xeb\x60\x29\xbb\x0f\x05\x07\x39\x61\xb1\xd1\x4f\xbe\x79",
		32);
	MD5Final(&md5);

	if (numKeys < MAX_KEYS && !memcmp(md5.digest, key+16, 16)) {
		int i;
		// does this key match any already registered?
		for (i=0; i<numKeys; i++) {
			if (!memcmp(key, keys[i], 16)) {
				Log(LF_INFO|LF_CONFIG, "Babylon: %d port key already loaded.", *key);
				return -EPERM;
			}
		}
		memcpy(keys[numKeys++], key, 16);
		nr_channels[1] += *key;
		Log(LF_INFO|LF_CONFIG, "Babylon: Additional %d port key loaded.", *key);
		return nr_channels[1];
	}
	return -EPERM;
}

int RegisterChannel(channel_t *ch)
{
	CLink *link;

	DebugEnter("RegisterChannel()");

	/* Make sure the version is OK */
	if (ch->link) {
		Log(LF_ERROR|LF_IPC, "%s: hannel already registered", ch->device_name);
		DebugReturn(-EBUSY);
	}

	if (ch->dev_class && !strcmp(ch->dev_class, "pppoe"))
		link = new pppoe_session(ch);
	else
		link = new CLink(ch);

	ch->link = link;
	if(!link) {
		Log(LF_ERROR|LF_IPC, "Error allocating memory for link");
		DebugReturn(-ENOMEM);
	}

	if (ch->link->reopen(1)) {
		Log(LF_ERROR|LF_IPC, "Error reopening channel: %s", strerror(errno));
		delete link;
		ch->link = NULL;
		DebugReturn(-EIO);
	}
	
	/*
	 * Set the link options from global defaults
	 */
	link->m_ldisc = next_ldisc++;

	nr_channels[0]++;
	DebugReturn(0);
}

void UnregisterChannel(channel_t *ch)
{
	CLink **lh;

	/* Find the channel on the list */
	for(lh = &linkListHead ; *lh != NULL && (*lh)->m_channel != ch ; lh = &(*lh)->m_next )
		;
	if (!*lh) {
		Log(LF_ERROR|LF_IPC, "%s: channel not on list!", ch->device_name);
		return;
	}

	/* now that we've found the channel - unregister it */
	if(ch->link != NULL)
		delete (CLink*)ch->link;

	nr_channels[0]--;
}

/*
 * Callback function for GetConfig.  Takes the
 * returned OptionSet_t and matches a link
 */
void DialGotConfig(void *, OptionSet_t *options)
{
	CLink *tch = linkListHead;
	DialResponse_t *dr;
	int i;

	DebugEnter("DialGotConfig()");

	dr = new DialResponse_t;
	if(dr == NULL) {
		Log(LF_DEBUG|LF_CALL, "Out of memory");
		DebugVoidReturn;
	}
	dr->call = options->call;

	if (!options->is_valid) {
		strcpy(dr->msg, "No valid config entry");
		dr->status = -2;
		goto out_failed;
	}

	Log(LF_DEBUG|LF_IPC, "Got valid configuration (Call_Ident %p)", options->call);
	//
	// Do the matching here
	//
	if (options->call->ch) {
		tch = options->call->ch->link;
	} else if(options->port[0] != '\0') {
		//
		// We have a port to match on
		//
		Log(LF_DEBUG|LF_IPC, "Attempting to match on port %s", 
				options->port);
		while((tch != NULL) && (strcmp(options->port, tch->m_channel->device_name) != 0))
			tch = tch->m_next;
	}
	else if(options->dev_class[0] != '\0') {
		int retry = 1;
		//
		// Attempting a match on device class
		//
		Log(LF_DEBUG|LF_IPC, "Attempting to match on port %s", 
			options->dev_class);

		while((tch != NULL) &&
		      ((strcmp(options->dev_class, tch->m_channel->dev_class) != 0) ||
		      (tch->m_channel->state != CS_IDLE)))
			tch = tch->m_next;

		if (!tch && retry && !strcmp(options->dev_class, "pppoe")) {
			tch = new pppoe_session(NULL, 0, NULL);
			if (tch->reopen(0)) {	/* failed to open? */
				delete tch;
				tch = NULL;
			}
		}
	}
	else {
		// 
		// Just try to find an idle link to dial on
		//
		Log(LF_DEBUG|LF_IPC, "Attempting to find idle link");
		while((tch != NULL) && (tch->m_channel->state != CS_IDLE))
			tch = tch->m_next;
	}

	if ((tch == NULL) || (tch->m_channel->state != CS_IDLE)) {
		//
		// No link
		//
		Log(LF_NOTICE|LF_IPC, "%s: Link in use or no link available, cancelled",
			options->site);
		strcpy(dr->msg, "No matching channel available");
		dr->status = -2;
		goto out_failed;
	}

	//
	// We found a link to dial on
	//
	
	//
	// First set the policy for the session if
	// necessary
	//
	if (options->pol) {
		SetPolicy(PSCOPE_SESSION, tch->m_channel->device_name, options->pol);
		delete options->pol;
		options->pol = NULL;
	}	
			
	tch->m_interface = FindIfaceDialing(options->call);	/* static interface a link *should* be added to */
	tch->Open();
	tch->ifOptions.Set(*options);

	Log(LF_DEBUG|LF_IPC, "Netmask = %x", tch->ifOptions.netmask);

	// Copy in the real port and class name
	strcpy(tch->ifOptions.dev_class, tch->m_channel->dev_class);
	strcpy(tch->ifOptions.port, tch->m_channel->device_name);

	// Dial the link
	for (i=0; tch->ifOptions.phone[i] || (-1 != (i = -1)); i++)
		if (('/' == tch->ifOptions.phone[i] || ';' == tch->ifOptions.phone[i]) &&
		    !(tch->ifOptions.phone[i] = 0))
			break;
	Log(LF_INFO|LF_IPC, "%s: Dialing %s... (%s)", tch->m_channel->device_name, 
		tch->ifOptions.phone, tch->ifOptions.site);
	Log(LF_DEBUG|LF_IPC, "Config is %s %s", 
		tch->ifOptions.is_valid ? "Valid" : "Invalid",
		options->is_valid ? "Valid" : "Invalid");
	dr->status = 0;
	strcpy(dr->msg, "Dialing...");
	DialReport(dr);
	if (tch->ifOptions.phone[0]) {
		dr->status = tch->Connect(tch->ifOptions.phone, tch->ifOptions.call_info);
		if (dr->status) {
			sprintf(dr->msg, "Connect: %d", dr->status);
			dr->status = -2;
			DialReport(dr);
			RemoveLinkDialing(options->call);
			tch->m_interface = NULL;
		}
	} else {
		strcpy(dr->msg, "Invalid phone number");
		dr->status = -2;
		DialReport(dr);
		RemoveLinkDialing(options->call);
		tch->m_interface = NULL;
	}

	if (i != -1)
		tch->ifOptions.phone[i] = '/';
	
	delete dr;
	DebugVoidReturn;

out_failed:
	DialReport(dr);
	RemoveLinkDialing(options->call);
	delete dr;
	DebugVoidReturn;
}