ipcp.c

vxworks的tcpip协议栈源码

	    ciaddr2 = htonl(tl);
	    IPCPDEBUG((LOG_INFO, "%s)", ip_ntoa(ciaddr2)));
	    if (ciaddr2 != wo->ouraddr) {
                if (ciaddr2 == 0 || !wo->accept_local) {
                    orc = CONFNAK;
                    if (!reject_if_disagree) {
                        DECPTR(sizeof (long), p);
                        tl = ntohl(wo->ouraddr);
                        PUTLONG(tl, p);
                    }
                } else {
                    go->ouraddr = ciaddr2;      /* accept peer's idea */
                }
            }

	    ho->neg_addr = 1;
	    ho->old_addrs = 1;
	    ho->hisaddr = ciaddr1;
	    ho->ouraddr = ciaddr2;
	    break;

	case CI_ADDR:
	    IPCPDEBUG((LOG_INFO, "ipcp: received ADDR "));

	    if (!ao->neg_addr ||
		cilen != CILEN_ADDR) {	/* Check CI length */
		orc = CONFREJ;		/* Reject CI */
		break;
	    }

	    /*
	     * If he has no address, or if we both have his address but
	     * disagree about it, then NAK it with our idea.
	     * In particular, if we don't know his address, but he does,
	     * then accept it.
	     */
	    GETLONG(tl, p);	/* Parse source address (his) */
	    ciaddr1 = htonl(tl);
	    IPCPDEBUG((LOG_INFO, "(%s)", ip_ntoa(ciaddr1)));
            if (ciaddr1 != wo->hisaddr
                && (ciaddr1 == 0 || !wo->accept_remote)) {
                orc = CONFNAK;
                if (!reject_if_disagree) {
                    DECPTR(sizeof (long), p);
                    tl = ntohl(wo->hisaddr);
                    PUTLONG(tl, p);
                }
            }

	    ho->neg_addr = 1;
	    ho->hisaddr = ciaddr1;
	    break;
	
	case CI_COMPRESSTYPE:
	    IPCPDEBUG((LOG_INFO, "ipcp: received COMPRESSTYPE "));
	    if (!ao->neg_vj ||
		(cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) {
		orc = CONFREJ;
		break;
	    }
	    GETSHORT(cishort, p);
	    IPCPDEBUG((LOG_INFO, "(%d)", cishort));

	    if (!(cishort == IPCP_VJ_COMP ||
		  (cishort == IPCP_VJ_COMP_OLD && cilen == CILEN_COMPRESS))) {
		orc = CONFREJ;
		break;
	    }

	    ho->neg_vj = 1;
	    ho->vj_protocol = cishort;
	    if (cilen == CILEN_VJ) {
		GETCHAR(maxslotindex, p);
		if (maxslotindex > ao->maxslotindex) { 
		    orc = CONFNAK;
		    if (!reject_if_disagree){
			DECPTR(1, p);
			PUTCHAR(ao->maxslotindex, p);
		    }
		}
		GETCHAR(cflag, p);
		if (cflag && !ao->cflag) {
		    orc = CONFNAK;
		    if (!reject_if_disagree){
			DECPTR(1, p);
			PUTCHAR(wo->cflag, p);
		    }
		}
                ho->maxslotindex = maxslotindex;
                ho->cflag = wo->cflag;
            } else {
                ho->old_vj = 1;
                ho->maxslotindex = MAX_STATES - 1;
                ho->cflag = 1;
            }
            break;

	default:
	    orc = CONFREJ;
	    break;
	}

endswitch:
	IPCPDEBUG((LOG_INFO, " (%s)", CODENAME(orc)));

	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 */
	    else {
		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((char *)cip, (char *)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 CI_ADDR option appended.  We assume the
     * input buffer is long enough that we can append the extra
     * option safely.
     */
    if (rc != CONFREJ && !ho->neg_addr &&
	wo->req_addr && !reject_if_disagree) {
	if (rc == CONFACK) {
	    rc = CONFNAK;
	    ucp = inp;			/* reset pointer */
	    wo->req_addr = 0;		/* don't ask again */
	}
	PUTCHAR(CI_ADDR, ucp);
	PUTCHAR(CILEN_ADDR, ucp);
	tl = ntohl(wo->hisaddr);
	PUTLONG(tl, ucp);
    }

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


/*
 * ipcp_up - IPCP has come UP.
 *
 * Configure the IP network interface appropriately and bring it up.
 */
static void
ipcp_up(f)
    fsm *f;
{
    u_long mask;
    ipcp_options *ho = &ppp_if[f->unit]->ipcp_hisoptions;
    ipcp_options *go = &ppp_if[f->unit]->ipcp_gotoptions;

    IPCPDEBUG((LOG_INFO, "ipcp: up"));
    go->default_route = 0;
    go->proxy_arp = 0;

    /*
     * We must have a non-zero IP address for both ends of the link.
     */
    if (!ho->neg_addr)
	ho->hisaddr = ppp_if[f->unit]->ipcp_wantoptions.hisaddr;

    if (ho->hisaddr == 0) {
	syslog(LOG_ERR, "Could not determine remote IP address");
	ipcp_close(f->unit);
	return;
    }
    if (go->ouraddr == 0) {
	syslog(LOG_ERR, "Could not determine local IP address");
	ipcp_close(f->unit);
	return;
    }

    /*
     * Check that the peer is allowed to use the IP address it wants.
     */
    if (!auth_ip_addr(f->unit, ho->hisaddr)) {
	syslog(LOG_ERR, "Peer is not authorized to use remote address %s",
	       ip_ntoa(ho->hisaddr));
	ipcp_close(f->unit);
	return;
    }

    syslog (LOG_NOTICE, "local  IP address %s", ip_ntoa(go->ouraddr));
    syslog (LOG_NOTICE, "remote IP address %s", ip_ntoa(ho->hisaddr));

    /*
     * Set IP addresses and (if specified) netmask.
     */
    mask = GetMask(go->ouraddr);
    if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
	IPCPDEBUG((LOG_WARNING, "sifaddr failed"));
	ipcp_close(f->unit);
	return;
    }

    /* set tcp compression */
    sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex);

    /* bring the interface up for IP */
    if (!sifup(f->unit)) {
	IPCPDEBUG((LOG_WARNING, "sifup failed"));
	ipcp_close(f->unit);
	return;
    }

    /* assign a default route through the interface if required */
    if (ppp_if[f->unit]->ipcp_wantoptions.default_route) 
	if (sifdefaultroute(f->unit, ho->hisaddr))
	    go->default_route = 1;

    /* Make a proxy ARP entry if requested. */
    if (ppp_if[f->unit]->ipcp_wantoptions.proxy_arp)
	if (sifproxyarp(f->unit, ho->hisaddr))
	    go->proxy_arp = 1;
}


/*
 * ipcp_down - IPCP has gone DOWN.
 *
 * Take the IP network interface down, clear its addresses
 * and delete routes through it.
 */
static void
ipcp_down(f)
    fsm *f;
{
    u_long ouraddr, hisaddr;

    IPCPDEBUG((LOG_INFO, "ipcp: down"));

    ouraddr = ppp_if[f->unit]->ipcp_gotoptions.ouraddr;
    hisaddr = ppp_if[f->unit]->ipcp_hisoptions.hisaddr;
    if (ppp_if[f->unit]->ipcp_gotoptions.proxy_arp)
	cifproxyarp(f->unit, hisaddr);
    if (ppp_if[f->unit]->ipcp_gotoptions.default_route) 
	cifdefaultroute(f->unit, hisaddr);
    sifdown(f->unit);
    cifaddr(f->unit, ouraddr, hisaddr);
}

#ifdef	notyet
/*
 * ipcp_script - Execute a script with arguments
 * interface-name tty-name speed local-IP remote-IP.
 */
static void
ipcp_script(f, script)
    fsm *f;
    char *script;
{
    char strspeed[32], strlocal[32], strremote[32];
    char *argv[8];

    sprintf(strspeed, "%d", ppp_if[f->unit]->baud_rate);
    strcpy(strlocal, ip_ntoa(ppp_if[f->unit]->ipcp_gotoptions.ouraddr));
    strcpy(strremote, ip_ntoa(ppp_if[f->unit]->ipcp_hisoptions.hisaddr));

    argv[0] = script;
    argv[1] = ppp_if[f->unit]->ifname;
    argv[2] = ppp_if[f->unit]->devname;
    argv[3] = strspeed;
    argv[4] = strlocal;
    argv[5] = strremote;
    argv[6] = NULL;
    run_program(script, argv, 0);
}
#endif	/* notyet */

/*
 * ipcp_printpkt - print the contents of an IPCP packet.
 */
char *ipcp_codenames[] = {
    "ConfReq", "ConfAck", "ConfNak", "ConfRej",
    "TermReq", "TermAck", "CodeRej"
};

int
ipcp_printpkt(p, plen, printer, arg)
    u_char *p;
    int plen;
    void (*printer)();
    void *arg;
{
    int code, id, len, olen;
    u_char *pstart, *optend;
    u_short cishort;
    u_long 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(ipcp_codenames) / sizeof(char *))
        printer(arg, " %s", ipcp_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 < 2 || olen > len) {
                break;
            }
            printer(arg, " <");
            len -= olen;
            optend = p + olen;
            switch (code) {
            case CI_ADDRS:
                if (olen == CILEN_ADDRS) {
                    p += 2;
                    GETLONG(cilong, p);
                    printer(arg, "addrs %s", ip_ntoa(htonl(cilong)));
                    GETLONG(cilong, p);
                    printer(arg, " %s", ip_ntoa(htonl(cilong)));
                }
                break;
            case CI_COMPRESSTYPE:
                if (olen >= CILEN_COMPRESS) {
                    p += 2;
                    GETSHORT(cishort, p);
                    printer(arg, "compress ");
                    switch (cishort) {
                    case IPCP_VJ_COMP:
                        printer(arg, "VJ");
                        break;
                    case IPCP_VJ_COMP_OLD:
                        printer(arg, "old-VJ");
                        break;
                    default:
                        printer(arg, "0x%x", cishort);
                    }
                }
                break;
            case CI_ADDR:
                if (olen == CILEN_ADDR) {
                    p += 2;
                    GETLONG(cilong, p);
                    printer(arg, "addr %s", ip_ntoa(htonl(cilong)));
                }
                break;
            }
            while (p < optend) {
                GETCHAR(code, p);
                printer(arg, " %.2x", code);
            }
            printer(arg, ">");
        }
        break;
    }

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

    return p - pstart;
}