if_spppsubr.c

基于组件方式开发操作系统的OSKIT源代码

		break;
	case STATE_STARTING:
		sp->rst_counter[cp->protoidx] = sp->lcp.max_configure;
		(cp->scr)(sp);
		sppp_cp_change_state(cp, sp, STATE_REQ_SENT);
		break;
	default:
		printf(SPP_FMT "%s illegal up in state %s\n",
		       SPP_ARGS(ifp), cp->name,
		       sppp_state_name(sp->state[cp->protoidx]));
	}
}

static void
sppp_down_event(const struct cp *cp, struct sppp *sp)
{
	STDDCL;

	if (debug)
		log(LOG_DEBUG, SPP_FMT "%s down(%s)\n",
		    SPP_ARGS(ifp), cp->name,
		    sppp_state_name(sp->state[cp->protoidx]));

	switch (sp->state[cp->protoidx]) {
	case STATE_CLOSED:
	case STATE_CLOSING:
		sppp_cp_change_state(cp, sp, STATE_INITIAL);
		break;
	case STATE_STOPPED:
		sppp_cp_change_state(cp, sp, STATE_STARTING);
		(cp->tls)(sp);
		break;
	case STATE_STOPPING:
	case STATE_REQ_SENT:
	case STATE_ACK_RCVD:
	case STATE_ACK_SENT:
		sppp_cp_change_state(cp, sp, STATE_STARTING);
		break;
	case STATE_OPENED:
		(cp->tld)(sp);
		sppp_cp_change_state(cp, sp, STATE_STARTING);
		break;
	default:
		printf(SPP_FMT "%s illegal down in state %s\n",
		       SPP_ARGS(ifp), cp->name,
		       sppp_state_name(sp->state[cp->protoidx]));
	}
}


static void
sppp_open_event(const struct cp *cp, struct sppp *sp)
{
	STDDCL;

	if (debug)
		log(LOG_DEBUG, SPP_FMT "%s open(%s)\n",
		    SPP_ARGS(ifp), cp->name,
		    sppp_state_name(sp->state[cp->protoidx]));

	switch (sp->state[cp->protoidx]) {
	case STATE_INITIAL:
		sppp_cp_change_state(cp, sp, STATE_STARTING);
		(cp->tls)(sp);
		break;
	case STATE_STARTING:
		break;
	case STATE_CLOSED:
		sp->rst_counter[cp->protoidx] = sp->lcp.max_configure;
		(cp->scr)(sp);
		sppp_cp_change_state(cp, sp, STATE_REQ_SENT);
		break;
	case STATE_STOPPED:
	case STATE_STOPPING:
	case STATE_REQ_SENT:
	case STATE_ACK_RCVD:
	case STATE_ACK_SENT:
	case STATE_OPENED:
		break;
	case STATE_CLOSING:
		sppp_cp_change_state(cp, sp, STATE_STOPPING);
		break;
	}
}


static void
sppp_close_event(const struct cp *cp, struct sppp *sp)
{
	STDDCL;

	if (debug)
		log(LOG_DEBUG, SPP_FMT "%s close(%s)\n",
		    SPP_ARGS(ifp), cp->name,
		    sppp_state_name(sp->state[cp->protoidx]));

	switch (sp->state[cp->protoidx]) {
	case STATE_INITIAL:
	case STATE_CLOSED:
	case STATE_CLOSING:
		break;
	case STATE_STARTING:
		sppp_cp_change_state(cp, sp, STATE_INITIAL);
		(cp->tlf)(sp);
		break;
	case STATE_STOPPED:
		sppp_cp_change_state(cp, sp, STATE_CLOSED);
		break;
	case STATE_STOPPING:
		sppp_cp_change_state(cp, sp, STATE_CLOSING);
		break;
	case STATE_OPENED:
		(cp->tld)(sp);
		/* fall through */
	case STATE_REQ_SENT:
	case STATE_ACK_RCVD:
	case STATE_ACK_SENT:
		sp->rst_counter[cp->protoidx] = sp->lcp.max_terminate;
		sppp_cp_send(sp, cp->proto, TERM_REQ, ++sp->pp_seq, 0, 0);
		sppp_cp_change_state(cp, sp, STATE_CLOSING);
		break;
	}
}

static void
sppp_to_event(const struct cp *cp, struct sppp *sp)
{
	STDDCL;
	int s;

	s = splimp();
	if (debug)
		log(LOG_DEBUG, SPP_FMT "%s TO(%s) rst_counter = %d\n",
		    SPP_ARGS(ifp), cp->name,
		    sppp_state_name(sp->state[cp->protoidx]),
		    sp->rst_counter[cp->protoidx]);

	if (--sp->rst_counter[cp->protoidx] < 0)
		/* TO- event */
		switch (sp->state[cp->protoidx]) {
		case STATE_CLOSING:
			sppp_cp_change_state(cp, sp, STATE_CLOSED);
			(cp->tlf)(sp);
			break;
		case STATE_STOPPING:
			sppp_cp_change_state(cp, sp, STATE_STOPPED);
			(cp->tlf)(sp);
			break;
		case STATE_REQ_SENT:
		case STATE_ACK_RCVD:
		case STATE_ACK_SENT:
			sppp_cp_change_state(cp, sp, STATE_STOPPED);
			(cp->tlf)(sp);
			break;
		}
	else
		/* TO+ event */
		switch (sp->state[cp->protoidx]) {
		case STATE_CLOSING:
		case STATE_STOPPING:
			sppp_cp_send(sp, cp->proto, TERM_REQ, ++sp->pp_seq,
				     0, 0);
			TIMEOUT(cp->TO, (void *)sp, sp->lcp.timeout, 
			    sp->ch[cp->protoidx]);
			break;
		case STATE_REQ_SENT:
		case STATE_ACK_RCVD:
			(cp->scr)(sp);
			/* sppp_cp_change_state() will restart the timer */
			sppp_cp_change_state(cp, sp, STATE_REQ_SENT);
			break;
		case STATE_ACK_SENT:
			(cp->scr)(sp);
			TIMEOUT(cp->TO, (void *)sp, sp->lcp.timeout,
			    sp->ch[cp->protoidx]);
			break;
		}

	splx(s);
}

/*
 * Change the state of a control protocol in the state automaton.
 * Takes care of starting/stopping the restart timer.
 */
void
sppp_cp_change_state(const struct cp *cp, struct sppp *sp, int newstate)
{
	sp->state[cp->protoidx] = newstate;

	UNTIMEOUT(cp->TO, (void *)sp, sp->ch[cp->protoidx]);
	switch (newstate) {
	case STATE_INITIAL:
	case STATE_STARTING:
	case STATE_CLOSED:
	case STATE_STOPPED:
	case STATE_OPENED:
		break;
	case STATE_CLOSING:
	case STATE_STOPPING:
	case STATE_REQ_SENT:
	case STATE_ACK_RCVD:
	case STATE_ACK_SENT:
		TIMEOUT(cp->TO, (void *)sp, sp->lcp.timeout, 
		    sp->ch[cp->protoidx]);
		break;
	}
}
/*
 *--------------------------------------------------------------------------*
 *                                                                          *
 *                         The LCP implementation.                          *
 *                                                                          *
 *--------------------------------------------------------------------------*
 */
static void
sppp_lcp_init(struct sppp *sp)
{
	sp->lcp.opts = (1 << LCP_OPT_MAGIC);
	sp->lcp.magic = 0;
	sp->state[IDX_LCP] = STATE_INITIAL;
	sp->fail_counter[IDX_LCP] = 0;
	sp->lcp.protos = 0;
	sp->lcp.mru = sp->lcp.their_mru = PP_MTU;

	/*
	 * Initialize counters and timeout values.  Note that we don't
	 * use the 3 seconds suggested in RFC 1661 since we are likely
	 * running on a fast link.  XXX We should probably implement
	 * the exponential backoff option.  Note that these values are
	 * relevant for all control protocols, not just LCP only.
	 */
	sp->lcp.timeout = 1 * hz;
	sp->lcp.max_terminate = 2;
	sp->lcp.max_configure = 10;
	sp->lcp.max_failure = 10;
#if defined(__FreeBSD__) && __FreeBSD__ >= 3
	callout_handle_init(&sp->ch[IDX_LCP]);
#endif
}

static void
sppp_lcp_up(struct sppp *sp)
{
	STDDCL;

	/*
	 * If this interface is passive or dial-on-demand, and we are
	 * still in Initial state, it means we've got an incoming
	 * call.  Activate the interface.
	 */
	if ((ifp->if_flags & (IFF_AUTO | IFF_PASSIVE)) != 0) {
		if (debug)
			log(LOG_DEBUG,
			    SPP_FMT "Up event", SPP_ARGS(ifp));
		ifp->if_flags |= IFF_RUNNING;
		if (sp->state[IDX_LCP] == STATE_INITIAL) {
			if (debug)
				addlog("(incoming call)\n");
			sp->pp_flags |= PP_CALLIN;
			lcp.Open(sp);
		} else if (debug)
			addlog("\n");
	}

	sppp_up_event(&lcp, sp);
}

static void
sppp_lcp_down(struct sppp *sp)
{
	STDDCL;

	sppp_down_event(&lcp, sp);

	/*
	 * If this is neither a dial-on-demand nor a passive
	 * interface, simulate an ``ifconfig down'' action, so the
	 * administrator can force a redial by another ``ifconfig
	 * up''.  XXX For leased line operation, should we immediately
	 * try to reopen the connection here?
	 */
	if ((ifp->if_flags & (IFF_AUTO | IFF_PASSIVE)) == 0) {
		log(LOG_INFO,
		    SPP_FMT "Down event, taking interface down.\n",
		    SPP_ARGS(ifp));
		if_down(ifp);
	} else {
		if (debug)
			log(LOG_DEBUG,
			    SPP_FMT "Down event (carrier loss)\n",
			    SPP_ARGS(ifp));
	}
	sp->pp_flags &= ~PP_CALLIN;
	if (sp->state[IDX_LCP] != STATE_INITIAL)
		lcp.Close(sp);
	ifp->if_flags &= ~IFF_RUNNING;
}

static void
sppp_lcp_open(struct sppp *sp)
{
	/*
	 * If we are authenticator, negotiate LCP_AUTH
	 */
	if (sp->hisauth.proto != 0)
		sp->lcp.opts |= (1 << LCP_OPT_AUTH_PROTO);
	else
		sp->lcp.opts &= ~(1 << LCP_OPT_AUTH_PROTO);
	sp->pp_flags &= ~PP_NEEDAUTH;
	sppp_open_event(&lcp, sp);
}

static void
sppp_lcp_close(struct sppp *sp)
{
	sppp_close_event(&lcp, sp);
}

static void
sppp_lcp_TO(void *cookie)
{
	sppp_to_event(&lcp, (struct sppp *)cookie);
}

/*
 * Analyze a configure request.  Return true if it was agreeable, and
 * caused action sca, false if it has been rejected or nak'ed, and
 * caused action scn.  (The return value is used to make the state
 * transition decision in the state automaton.)
 */
static int
sppp_lcp_RCR(struct sppp *sp, struct lcp_header *h, int len)
{
	STDDCL;
	u_char *buf, *r, *p;
	int origlen, rlen;
	u_long nmagic;
	u_short authproto;

	len -= 4;
	origlen = len;
	buf = r = malloc (len, M_TEMP, M_NOWAIT);
	if (! buf)
		return (0);

	if (debug)
		log(LOG_DEBUG, SPP_FMT "lcp parse opts: ",
		    SPP_ARGS(ifp));

	/* pass 1: check for things that need to be rejected */
	p = (void*) (h+1);
	for (rlen=0; len>1 && p[1]; len-=p[1], p+=p[1]) {
		if (debug)
			addlog(" %s ", sppp_lcp_opt_name(*p));
		switch (*p) {
		case LCP_OPT_MAGIC:
			/* Magic number. */
			/* fall through, both are same length */
		case LCP_OPT_ASYNC_MAP:
			/* Async control character map. */
			if (len >= 6 || p[1] == 6)
				continue;
			if (debug)
				addlog("[invalid] ");
			break;
		case LCP_OPT_MRU:
			/* Maximum receive unit. */
			if (len >= 4 && p[1] == 4)
				continue;
			if (debug)
				addlog("[invalid] ");
			break;
		case LCP_OPT_AUTH_PROTO:
			if (len < 4) {
				if (debug)
					addlog("[invalid] ");
				break;
			}
			authproto = (p[2] << 8) + p[3];
			if (authproto == PPP_CHAP && p[1] != 5) {
				if (debug)
					addlog("[invalid chap len] ");
				break;
			}
			if (sp->myauth.proto == 0) {
				/* we are not configured to do auth */
				if (debug)
					addlog("[not configured] ");
				break;
			}
			/*
			 * Remote want us to authenticate, remember this,
			 * so we stay in PHASE_AUTHENTICATE after LCP got
			 * up.
			 */
			sp->pp_flags |= PP_NEEDAUTH;
			continue;
		default:
			/* Others not supported. */
			if (debug)
				addlog("[rej] ");
			break;
		}
		/* Add the option to rejected list. */
		bcopy (p, r, p[1]);
		r += p[1];
		rlen += p[1];
	}
	if (rlen) {
		if (debug)
			addlog(" send conf-rej\n");
		sppp_cp_send (sp, PPP_LCP, CONF_REJ, h->ident, rlen, buf);
		return 0;
	} else if (debug)
		addlog("\n");

	/*
	 * pass 2: check for option values that are unacceptable and
	 * thus require to be nak'ed.
	 */
	if (debug)
		log(LOG_DEBUG, SPP_FMT "lcp parse opt values: ",
		    SPP_ARGS(ifp));

	p = (void*) (h+1);
	len = origlen;
	for (rlen=0; len>1 && p[1]; len-=p[1], p+=p[1]) {
		if (debug)
			addlog(" %s ", sppp_lcp_opt_name(*p));
		switch (*p) {
		case LCP_OPT_MAGIC:
			/* Magic number -- extract. */
			nmagic = (u_long)p[2] << 24 |
				(u_long)p[3] << 16 | p[4] << 8 | p[5];
			if (nmagic != sp->lcp.magic) {
				if (debug)
					addlog("0x%lx ", nmagic);
				continue;
			}
			/*
			 * Local and remote magics equal -- loopback?
			 */
			if (sp->pp_loopcnt >= MAXALIVECNT*5) {
				printf (SPP_FMT "loopback\n",
					SPP_ARGS(ifp));
				sp->pp_loopcnt = 0;
				if (ifp->if_flags & IFF_UP) {
					if_down(ifp);
					sppp_qflush(&sp->pp_cpq);
					/* XXX ? */
					lcp.Down(sp);
					lcp.Up(sp);
				}
			} else if (debug)
				addlog("[glitch] ");
			++sp->pp_loopcnt;
			/*
			 * We negate our magic here, and NAK it.  If
			 * we see it later in an NAK packet, we
			 * suggest a new one.
			 */
			nmagic = ~sp->lcp.magic;
			/* Gonna NAK it. */
			p[2] = nmagic >> 24;
			p[3] = nmagic >> 16;
			p[4] = nmagic >> 8;
			p[5] = nmagic;
			break;

		case LCP_OPT_ASYNC_MAP:
			/* Async control character map -- check to be zero. */
			if (! p[2] && ! p[3] && ! p[4] && ! p[5]) {
				if (debug)
					addlog("[empty] ");
				continue;
			}
			if (debug)
				addlog("[non-empty] ");
			/* suggest a zero one */
			p[2] = p[3] = p[4] = p[5] = 0;
			break;

		case LCP_OPT_MRU:
			/*
			 * Maximum receive unit.  Always agreeable,
			 * but ignored by now.
			 */
			sp->lcp.their_mru = p[2] * 256 + p[3];
			if (debug)
				addlog("%lu ", sp->lcp.their_mru);
			continue;

		case LCP_OPT_AUTH_PROTO:
			authproto = (p[2] << 8) + p[3];
			if (sp->myauth.proto != authproto) {
				/* not agreed, nak */
				if (debug)
					addlog("[mine %s != his %s] ",
					       sppp_proto_name(sp->hisauth.proto),
					       sppp_proto_name(authproto));
				p[2] = sp->myauth.proto >> 8;
				p[3] = sp->myauth.proto;
				break;
			}
			if (authproto == PPP_CHAP && p[4] != CHAP_MD5) {
				if (debug)
					addlog("[chap not MD5] ");
				p[4] = CHAP_MD5;
				break;
			}
			continue;
		}
		/* Add the option to nak'ed list. */
		bcopy (p, r, p[1]);
		r += p[1];
		rlen += p[1];
	}
	if (rlen) {
		if (++sp->fail_counter[IDX_LCP] >= sp->lcp.max_failure) {
			if (debug)
				addlog(" max_failure (%d) exceeded, "
				       "send conf-rej\n",
				       sp->lcp.max_failure);
			sppp_cp_send(sp, PPP_LCP, CONF_REJ, h->ident, rlen, buf);
		} else {