ipxcp.c

自己精简过的PPPD代码。在嵌入中应用可以更好的发挥。比原先的小了很多

		PUTLONG (wo->our_network, p);
		orc = CONFNAK;
/*
 * We don't have one. Reject the value.
 */
	    } else
		orc = CONFREJ;

	    break;
/*
 * The node number is required
 */
	case IPX_NODE_NUMBER:
	    /* if we wont negotiate the node number or the length is wrong
	       then reject the option */
	    if ( cilen != CILEN_NODEN ) {
		orc = CONFREJ;
		break;
	    }

	    copy_node (p, ho->his_node);
	    ho->neg_node = 1;
/*
 * If the remote does not have a number and we do then NAK it with the value
 * which we have for it. (We never have a default value of zero.)
 */
	    if (zero_node (ho->his_node)) {
		orc = CONFNAK;
		copy_node (wo->his_node, p);
		INCPTR (sizeof (wo->his_node), p);
		break;
	    }
/*
 * If you have given me the expected network node number then I'll accept
 * it now.
 */
	    if (compare_node (wo->his_node, ho->his_node)) {
		orc = CONFACK;
		ho->neg_node = 1;
		INCPTR (sizeof (wo->his_node), p);
		break;
	    }
/*
 * If his node number is the same as ours then ask him to try the next
 * value.
 */
	    if (compare_node (ho->his_node, go->our_node)) {
		inc_node (ho->his_node);
		orc = CONFNAK;
		copy_node (ho->his_node, p);
		INCPTR (sizeof (wo->his_node), p);
		break;
	    }
/*
 * If we don't accept a new value then NAK it.
 */
	    if (! ao->accept_remote) {
		copy_node (wo->his_node, p);
		INCPTR (sizeof (wo->his_node), p);
		orc = CONFNAK;
		break;
	    }
	    orc = CONFACK;
	    ho->neg_node = 1;
	    INCPTR (sizeof (wo->his_node), p);
	    break;
/*
 * Compression is not desired at this time. It is always rejected.
 */
	case IPX_COMPRESSION_PROTOCOL:
	    orc = CONFREJ;
	    break;
/*
 * The routing protocol is a bitmask of various types. Any combination
 * of the values RIP_SAP and NLSP are permissible. 'IPX_NONE' for no
 * routing protocol must be specified only once.
 */
	case IPX_ROUTER_PROTOCOL:
	    if ( !ao->neg_router || cilen < CILEN_PROTOCOL ) {
		orc = CONFREJ;
		break;		
	    }

	    GETSHORT (cishort, p);

	    if (wo->neg_router == 0) {
	        wo->neg_router = 1;
		wo->router     = BIT(IPX_NONE);
	    }

	    if ((cishort == IPX_NONE && ho->router != 0) ||
		(ho->router & BIT(IPX_NONE))) {
		orc = CONFREJ;
		break;
	    }

	    cishort = BIT(cishort);
	    if (ho->router & cishort) {
		orc = CONFREJ;
		break;
	    }

	    ho->router	  |= cishort;
	    ho->neg_router = 1;

	    /* Finally do not allow a router protocol which we do not
	       support. */

	    if ((cishort & (ao->router | BIT(IPX_NONE))) == 0) {
	        int protocol;

		if (cishort == BIT(NLSP) &&
		    (ao->router & BIT(RIP_SAP)) &&
		    !wo->tried_rip) {
		    protocol      = RIP_SAP;
		    wo->tried_rip = 1;
		} else
		    protocol = IPX_NONE;

		DECPTR (sizeof (u_int16_t), p);
		PUTSHORT (protocol, p);
		orc = CONFNAK;
	    }
	    break;
/*
 * The router name is advisorary. Just accept it if it is not too large.
 */
	case IPX_ROUTER_NAME:
	    if (cilen >= CILEN_NAME) {
		int name_size = cilen - CILEN_NAME;
		if (name_size > sizeof (ho->name))
		    name_size = sizeof (ho->name) - 1;
		memset (ho->name, 0, sizeof (ho->name));
		memcpy (ho->name, p, name_size);
		ho->name [name_size] = '\0';
		ho->neg_name = 1;
		orc = CONFACK;
		break;
	    }
	    orc = CONFREJ;
	    break;
/*
 * This is advisorary.
 */
	case IPX_COMPLETE:
	    if (cilen != CILEN_COMPLETE)
		orc = CONFREJ;
	    else {
		ho->neg_complete = 1;
		orc = CONFACK;
	    }
	    break;
/*
 * All other entries are not known at this time.
 */
	default:
	    orc = CONFREJ;
	    break;
	}
endswitch:
	if (orc == CONFACK &&		/* Good CI */
	    rc != CONFACK)		/*  but prior CI wasnt? */
	    continue;			/* Don't send this one */

	if (orc == CONFNAK) {		/* Nak this CI? */
	    if (reject_if_disagree)	/* Getting fed up with sending NAKs? */
		orc = CONFREJ;		/* Get tough if so */
	    if (rc == CONFREJ)		/* Rejecting prior CI? */
		continue;		/* Don't send this one */
	    if (rc == CONFACK) {	/* Ack'd all prior CIs? */
		rc  = CONFNAK;		/* Not anymore... */
		ucp = inp;		/* Backup */
	    }
	}

	if (orc == CONFREJ &&		/* Reject this CI */
	    rc != CONFREJ) {		/*  but no prior ones? */
	    rc = CONFREJ;
	    ucp = inp;			/* Backup */
	}

	/* Need to move CI? */
	if (ucp != cip)
	    BCOPY(cip, ucp, cilen);	/* Move it */

	/* Update output pointer */
	INCPTR(cilen, ucp);
    }

    /*
     * If we aren't rejecting this packet, and we want to negotiate
     * their address, and they didn't send their address, then we
     * send a NAK with a IPX_NODE_NUMBER option appended. We assume the
     * input buffer is long enough that we can append the extra
     * option safely.
     */

    if (rc != CONFREJ && !ho->neg_node &&
	wo->req_nn && !reject_if_disagree) {
	if (rc == CONFACK) {
	    rc = CONFNAK;
	    wo->req_nn = 0;		/* don't ask again */
	    ucp = inp;			/* reset pointer */
	}

	if (zero_node (wo->his_node))
	    inc_node (wo->his_node);

	PUTCHAR (IPX_NODE_NUMBER, ucp);
	PUTCHAR (CILEN_NODEN, ucp);
	copy_node (wo->his_node, ucp);
	INCPTR (sizeof (wo->his_node), ucp);
    }

    *len = ucp - inp;			/* Compute output length */
    IPXCPDEBUG(("ipxcp: returning Configure-%s", CODENAME(rc)));
    return (rc);			/* Return final code */
}

/*
 * ipxcp_up - IPXCP has come UP.
 *
 * Configure the IP network interface appropriately and bring it up.
 */

static void
ipxcp_up(f)
    fsm *f;
{
    int unit = f->unit;

    IPXCPDEBUG(("ipxcp: up"));

    /* The default router protocol is RIP/SAP. */
    if (ho->router == 0)
        ho->router = BIT(RIP_SAP);

    if (go->router == 0)
        go->router = BIT(RIP_SAP);

    /* Fetch the network number */
    if (!ho->neg_nn)
	ho->his_network = wo->his_network;

    if (!ho->neg_node)
	copy_node (wo->his_node, ho->his_node);

    if (!wo->neg_node && !go->neg_node)
	copy_node (wo->our_node, go->our_node);

    if (zero_node (go->our_node)) {
        static char errmsg[] = "Could not determine local IPX node address";
	if (debug)
	    error(errmsg);
	ipxcp_close(f->unit, errmsg);
	return;
    }

    go->network = go->our_network;
    if (ho->his_network != 0 && ho->his_network > go->network)
	go->network = ho->his_network;

    if (go->network == 0) {
        static char errmsg[] = "Can not determine network number";
	if (debug)
	    error(errmsg);
	ipxcp_close (unit, errmsg);
	return;
    }

    /* bring the interface up */
    if (!sifup(unit)) {
	if (debug)
	    warn("sifup failed (IPX)");
	ipxcp_close(unit, "Interface configuration failed");
	return;
    }
    ipxcp_is_up = 1;

    /* set the network number for IPX */
    if (!sipxfaddr(unit, go->network, go->our_node)) {
	if (debug)
	    warn("sipxfaddr failed");
	ipxcp_close(unit, "Interface configuration failed");
	return;
    }

    np_up(f->unit, PPP_IPX);

    /*
     * Execute the ipx-up script, like this:
     *	/etc/ppp/ipx-up interface tty speed local-IPX remote-IPX
     */

    ipxcp_script (f, _PATH_IPXUP);
}

/*
 * ipxcp_down - IPXCP has gone DOWN.
 *
 * Take the IP network interface down, clear its addresses
 * and delete routes through it.
 */

static void
ipxcp_down(f)
    fsm *f;
{
    IPXCPDEBUG(("ipxcp: down"));

    if (!ipxcp_is_up)
	return;
    ipxcp_is_up = 0;
    np_down(f->unit, PPP_IPX);
    cipxfaddr(f->unit);
    sifnpmode(f->unit, PPP_IPX, NPMODE_DROP);
    sifdown(f->unit);
    ipxcp_script (f, _PATH_IPXDOWN);
}


/*
 * ipxcp_finished - possibly shut down the lower layers.
 */
static void
ipxcp_finished(f)
    fsm *f;
{
    np_finished(f->unit, PPP_IPX);
}


/*
 * ipxcp_script - Execute a script with arguments
 * interface-name tty-name speed local-IPX remote-IPX networks.
 */
static void
ipxcp_script(f, script)
    fsm *f;
    char *script;
{
    char strspeed[32],	 strlocal[32],	   strremote[32];
    char strnetwork[32], strpid[32];
    char *argv[14],	 strproto_lcl[32], strproto_rmt[32];

    slprintf(strpid, sizeof(strpid), "%d", getpid());
    slprintf(strspeed, sizeof(strspeed),"%d", baud_rate);

    strproto_lcl[0] = '\0';
    if (go->neg_router && ((go->router & BIT(IPX_NONE)) == 0)) {
	if (go->router & BIT(RIP_SAP))
	    strlcpy (strproto_lcl, "RIP ", sizeof(strproto_lcl));
	if (go->router & BIT(NLSP))
	    strlcat (strproto_lcl, "NLSP ", sizeof(strproto_lcl));
    }

    if (strproto_lcl[0] == '\0')
	strlcpy (strproto_lcl, "NONE ", sizeof(strproto_lcl));

    strproto_lcl[strlen (strproto_lcl)-1] = '\0';

    strproto_rmt[0] = '\0';
    if (ho->neg_router && ((ho->router & BIT(IPX_NONE)) == 0)) {
	if (ho->router & BIT(RIP_SAP))
	    strlcpy (strproto_rmt, "RIP ", sizeof(strproto_rmt));
	if (ho->router & BIT(NLSP))
	    strlcat (strproto_rmt, "NLSP ", sizeof(strproto_rmt));
    }

    if (strproto_rmt[0] == '\0')
	strlcpy (strproto_rmt, "NONE ", sizeof(strproto_rmt));

    strproto_rmt[strlen (strproto_rmt)-1] = '\0';

    strlcpy (strnetwork, ipx_ntoa (go->network), sizeof(strnetwork));

    slprintf (strlocal, sizeof(strlocal), "%0.6B", go->our_node);

    slprintf (strremote, sizeof(strremote), "%0.6B", ho->his_node);

    argv[0]  = script;
    argv[1]  = ifname;
    argv[2]  = devnam;
    argv[3]  = strspeed;
    argv[4]  = strnetwork;
    argv[5]  = strlocal;
    argv[6]  = strremote;
    argv[7]  = strproto_lcl;
    argv[8]  = strproto_rmt;
    argv[9]  = go->name;
    argv[10] = ho->name;
    argv[11] = ipparam;
    argv[12] = strpid;
    argv[13] = NULL;
    run_program(script, argv, 0, NULL, NULL, 0);
}

/*
 * ipxcp_printpkt - print the contents of an IPXCP packet.
 */
static char *ipxcp_codenames[] = {
    "ConfReq", "ConfAck", "ConfNak", "ConfRej",
    "TermReq", "TermAck", "CodeRej"
};

static int
ipxcp_printpkt(p, plen, printer, arg)
    u_char *p;
    int plen;
    void (*printer) __P((void *, char *, ...));
    void *arg;
{
    int code, id, len, olen;
    u_char *pstart, *optend;
    u_short cishort;
    u_int32_t cilong;

    if (plen < HEADERLEN)
	return 0;
    pstart = p;
    GETCHAR(code, p);
    GETCHAR(id, p);
    GETSHORT(len, p);
    if (len < HEADERLEN || len > plen)
	return 0;

    if (code >= 1 && code <= sizeof(ipxcp_codenames) / sizeof(char *))
	printer(arg, " %s", ipxcp_codenames[code-1]);
    else
	printer(arg, " code=0x%x", code);
    printer(arg, " id=0x%x", id);
    len -= HEADERLEN;
    switch (code) {
    case CONFREQ:
    case CONFACK:
    case CONFNAK:
    case CONFREJ:
	/* print option list */
	while (len >= 2) {
	    GETCHAR(code, p);
	    GETCHAR(olen, p);
	    p -= 2;
	    if (olen < CILEN_VOID || olen > len) {
		break;
	    }
	    printer(arg, " <");
	    len -= olen;
	    optend = p + olen;
	    switch (code) {
	    case IPX_NETWORK_NUMBER:
		if (olen == CILEN_NETN) {
		    p += 2;
		    GETLONG(cilong, p);
		    printer (arg, "network %s", ipx_ntoa (cilong));
		}
		break;
	    case IPX_NODE_NUMBER:
		if (olen == CILEN_NODEN) {
		    p += 2;
		    printer (arg, "node ");
		    while (p < optend) {
			GETCHAR(code, p);
			printer(arg, "%.2x", (int) (unsigned int) (unsigned char) code);
		    }
		}
		break;
	    case IPX_COMPRESSION_PROTOCOL:
		if (olen == CILEN_COMPRESS) {
		    p += 2;
		    GETSHORT (cishort, p);
		    printer (arg, "compression %d", (int) cishort);
		}
		break;
	    case IPX_ROUTER_PROTOCOL:
		if (olen == CILEN_PROTOCOL) {
		    p += 2;
		    GETSHORT (cishort, p);
		    printer (arg, "router proto %d", (int) cishort);
		}
		break;
	    case IPX_ROUTER_NAME:
		if (olen >= CILEN_NAME) {
		    p += 2;
		    printer (arg, "router name \"");
		    while (p < optend) {
			GETCHAR(code, p);
			if (code >= 0x20 && code <= 0x7E)
			    printer (arg, "%c", (int) (unsigned int) (unsigned char) code);
			else
			    printer (arg, " \\%.2x", (int) (unsigned int) (unsigned char) code);
		    }
		    printer (arg, "\"");
		}
		break;
	    case IPX_COMPLETE:
		if (olen == CILEN_COMPLETE) {
		    p += 2;
		    printer (arg, "complete");
		}
		break;
	    default:
		break;
	    }

	    while (p < optend) {
		GETCHAR(code, p);
		printer(arg, " %.2x", (int) (unsigned int) (unsigned char) code);
	    }
	    printer(arg, ">");
	}
	break;

    case TERMACK:
    case TERMREQ:
	if (len > 0 && *p >= ' ' && *p < 0x7f) {
	    printer(arg, " ");
	    print_string(p, len, printer, arg);
	    p += len;
	    len = 0;
	}
	break;
    }

    /* print the rest of the bytes in the packet */
    for (; len > 0; --len) {
	GETCHAR(code, p);
	printer(arg, " %.2x", (int) (unsigned int) (unsigned char) code);
    }

    return p - pstart;
}
#endif /* ifdef IPX_CHANGE */