/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgment:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: src/sbin/routed/parms.c,v 1.9 2000/08/11 08:24:38 sheldonh Exp $
 */

#include "defs.h"
#include "pathnames.h"
#include <sys/stat.h>
#include <arpa/inet.h>
#include <ctype.h>

#define PARMS_MAXLINELEN        500
static struct parm *parms;
struct intnet *intnets;
struct r1net *r1nets;
struct tgate *tgates;

static void addroutefordefault(in_addr_t, in_addr_t, in_addr_t,
    uint32_t, uint16_t);

/* use configured parameters */
void
get_parms(struct interface *ifp)
{
        static boolean_t warned_auth_in, warned_auth_out;
        struct parm *parmp;
        int i, num_passwds = 0;

        if (ifp == NULL)
                return;

        /* get all relevant parameters */
        for (parmp = parms; parmp != NULL; parmp = parmp->parm_next) {
                if (parmp->parm_name[0] == '\0' ||
                    strcmp(ifp->int_name, parmp->parm_name) == 0 ||
                    (parmp->parm_name[0] == '\n' &&
                    on_net(ifp->int_addr,
                    parmp->parm_net, parmp->parm_mask))) {

                        /*
                         * This group of parameters is relevant,
                         * so get its settings
                         */
                        ifp->int_state |= parmp->parm_int_state;
                        for (i = 0; i < MAX_AUTH_KEYS; i++) {
                                if (parmp->parm_auth[i].type == RIP_AUTH_NONE ||
                                    num_passwds >= MAX_AUTH_KEYS)
                                        break;
                                ifp->int_auth[num_passwds++] =
                                    parmp->parm_auth[i];
                        }
                        if (parmp->parm_rdisc_pref != 0)
                                ifp->int_rdisc_pref = parmp->parm_rdisc_pref;
                        if (parmp->parm_rdisc_int != 0)
                                ifp->int_rdisc_int = parmp->parm_rdisc_int;
                        if (parmp->parm_d_metric != 0)
                                ifp->int_d_metric = parmp->parm_d_metric;
                        if (parmp->parm_ripout_addr != 0)
                                ifp->int_ripout_addr = parmp->parm_ripout_addr;
                }
        }

        /*
         * Set general defaults.
         *
         * Default poor-man's router discovery to a metric that will
         * be heard by old versions of `routed`.  They ignored received
         * routes with metric 15.
         */
        if ((ifp->int_state & IS_PM_RDISC) && ifp->int_d_metric == 0)
                ifp->int_d_metric = FAKE_METRIC;

        if (ifp->int_rdisc_int == 0)
                ifp->int_rdisc_int = DEF_MAXADVERTISEINTERVAL;

        if (!(ifp->int_if_flags & IFF_MULTICAST) &&
            !(ifp->int_state & IS_REMOTE))
                ifp->int_state |= IS_BCAST_RDISC;

        if (ifp->int_if_flags & IFF_POINTOPOINT) {
                ifp->int_state |= IS_BCAST_RDISC;
                /*
                 * By default, point-to-point links should be passive
                 * about router-discovery for the sake of demand-dialing.
                 */
                if (!(ifp->int_state & GROUP_IS_SOL_OUT))
                        ifp->int_state |= IS_NO_SOL_OUT;
                if (!(ifp->int_state & GROUP_IS_ADV_OUT))
                        ifp->int_state |= IS_NO_ADV_OUT;
        }

        if (0 != (ifp->int_state & (IS_PASSIVE | IS_REMOTE)))
                ifp->int_state |= IS_NO_RDISC;
        if (ifp->int_state & IS_PASSIVE)
                ifp->int_state |= IS_NO_RIP;

        if (!IS_RIP_IN_OFF(ifp->int_state) &&
            ifp->int_auth[0].type != RIP_AUTH_NONE &&
            !(ifp->int_state & IS_NO_RIPV1_IN) && !warned_auth_in) {
                writelog(LOG_WARNING, "RIPv1 input via %s"
                    " will be accepted without authentication",
                    ifp->int_name);
                warned_auth_in = _B_TRUE;
        }
        if (!IS_RIP_OUT_OFF(ifp->int_state) &&
            ifp->int_auth[0].type != RIP_AUTH_NONE &&
            !(ifp->int_state & IS_NO_RIPV1_OUT)) {
                if (!warned_auth_out) {
                        writelog(LOG_WARNING, "RIPv1 output via %s"
                            " will be sent without authentication",
                            ifp->int_name);
                        warned_auth_out = _B_TRUE;
                }
        }

        /*
         * If not overriden by the rip_neighbor option, set the
         * default address to which RIP packets will be sent on
         * this interface.
         */
        if (ifp->int_ripout_addr == 0) {
                if (ifp->int_state & IS_REMOTE) {
                        /*
                         * By definition we always send RIP packets to
                         * the address assigned to a remote interface.
                         */
                        ifp->int_ripout_addr = ifp->int_addr;
                } else if ((ifp->int_state & IS_NO_RIPV1_OUT) &&
                    (ifp->int_if_flags & IFF_MULTICAST) &&
                    !(ifp->int_state & IS_NO_RIP_MCAST)) {
                        /*
                         * If the interface is being used for RIPv2
                         * and it supports multicast, and if the user
                         * has not explicitely turned off multicast
                         * RIP output, send to the all RIP routers
                         * multicast address.
                         */
                        ifp->int_ripout_addr = htonl(INADDR_RIP_GROUP);
                } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
                        /*
                         * For point-to-point interfaces which don't
                         * fall into the two categories above, just
                         * send to the destination address of the
                         * interface.
                         */
                        ifp->int_ripout_addr = ifp->int_dstaddr;
                } else {
                        /* Otherwise, use the broadcast address. */
                        ifp->int_ripout_addr = ifp->int_brdaddr;
                }
        }
}


/*
 * Read a list of gateways from /etc/gateways and add them to our tables.
 *
 * This file contains a list of "remote" gateways.  That is usually
 * a gateway which we cannot immediately determine if it is present or
 * not as we can do for those provided by directly connected hardware.
 *
 * If a gateway is marked "passive" in the file, then we assume it
 * does not understand RIP and assume it is always present.  Those
 * not marked passive are treated as if they were directly connected
 * and assumed to be broken if they do not send us advertisements.
 * All remote interfaces are added to our list, and those not marked
 * passive are sent routing updates.
 *
 * A passive interface can also be local, hardware interface exempt
 * from RIP.
 */
void
gwkludge(void)
{
#define STR2(x) #x
#define STR(x)  STR2(x)

#define NETHOST_LEN     4
#define DNAME_LEN       MAXHOSTNAMELEN
#define GNAME_LEN       MAXHOSTNAMELEN
#define QUAL_LEN        8

        FILE *fp;
        char *p, *lptr;
        const char *cp;
        char lbuf[PARMS_MAXLINELEN], net_host[NETHOST_LEN + 1];
        char dname[MAXHOSTNAMELEN + 1];
        char gname[MAXHOSTNAMELEN + 1], qual[QUAL_LEN +1];
        struct interface *ifp;
        uint32_t dst, netmask, gate;
        int n;
        uint32_t lnum;
        struct stat sb;
        uint32_t state, metric;
        boolean_t default_dst;


        fp = fopen(PATH_GATEWAYS, "r");
        if (fp == NULL)
                return;

        if (0 > fstat(fileno(fp), &sb)) {
                msglog("fstat() failed: %s for  "PATH_GATEWAYS,
                    rip_strerror(errno));
                (void) fclose(fp);
                return;
        }

        for (lnum = 1; ; lnum++) {
                if (NULL == fgets(lbuf, sizeof (lbuf), fp))
                        break;

                /* Eliminate the /n character at the end of the lbuf */
                if (strlen(lbuf) > 0)
                        lbuf[strlen(lbuf) - 1] = '\0';

                /* Move lptr to the first non-space character */
                for (lptr = lbuf; isspace(*lptr); lptr++)
                        ;

                if (*lptr == '#' || *lptr == '\0')
                        continue;

                /* Move p to the end of the line */
                p = lptr + strlen(lptr) - 1;

                /* Skip all trailing spaces except escaped space */
                while (p > lptr && (isspace(*p) && *(p-1) != '\\'))
                        p--;

                /* truncate the line to remove trailing spaces */
                *++p = '\0';

                /* notice newfangled parameter lines */
                if (strncasecmp("net", lptr, 3) != 0 &&
                    strncasecmp("host", lptr, 4) != 0) {
                        cp = parse_parms(lptr, (sb.st_uid == 0 &&
                            !(sb.st_mode&(S_IRWXG|S_IRWXO))));
                        if (cp != 0)
                                msglog("%s in line %u of "PATH_GATEWAYS,
                                    cp, lnum);
                        continue;
                }

                /*
                 * Processes lines of the follwoing format:
                 * net|host <name>[/mask] gateway <Gname> metric <value>
                 * passive|active|extern
                 */
                qual[0] = '\0';
                n = sscanf(lptr, "%"STR(NETHOST_LEN)"s %"STR(DNAME_LEN)
                    "[^ \t] gateway %"STR(GNAME_LEN)"[^ / \t] metric %u %"
                    STR(QUAL_LEN)"s\n", net_host, dname, gname, &metric, qual);
                if (n != 4 && n != 5) {
                        msglog("bad "PATH_GATEWAYS" entry \"%s\"; %d values",
                            lptr, n);
                        continue;
                }
                if (metric >= HOPCNT_INFINITY) {
                        msglog("bad metric in "PATH_GATEWAYS" entry \"%s\"",
                            lptr);
                        continue;
                }
                default_dst = _B_FALSE;
                if (strcasecmp(net_host, "host") == 0) {
                        if (!gethost(dname, &dst)) {
                                msglog("bad host \"%s\" in "PATH_GATEWAYS
                                    " entry \"%s\"", dname, lptr);
                                continue;
                        }
                        netmask = HOST_MASK;
                } else if (strcasecmp(net_host, "net") == 0) {
                        if (!getnet(dname, &dst, &netmask)) {
                                msglog("bad net \"%s\" in "PATH_GATEWAYS
                                    " entry \"%s\"", dname, lptr);
                                continue;
                        }
                        default_dst = (dst == RIP_DEFAULT);
                        dst = htonl(dst); /* make network # into IP address */
                } else {
                        msglog("bad \"%s\" in "PATH_GATEWAYS
                            " entry \"%s\"", net_host, lptr);
                        continue;
                }

                if (!gethost(gname, &gate)) {
                        msglog("bad gateway \"%s\" in "PATH_GATEWAYS
                            " entry \"%s\"", gname, lptr);
                        continue;
                }

                if (strcasecmp(qual, "passive") == 0) {
                        /*
                         * Passive entries are not placed in our tables,
                         * only the kernel's, so we don't copy all of the
                         * external routing information within a net.
                         * Internal machines should use the default
                         * route to a suitable gateway (like us).
                         */
                        state = IS_REMOTE | IS_PASSIVE;
                        if (metric == 0)
                                metric = 1;

                } else if (strcasecmp(qual, "external") == 0) {
                        /*
                         * External entries are handled by other means
                         * such as EGP, and are placed only in the daemon
                         * tables to prevent overriding them with something
                         * else.
                         */
                        (void) strlcpy(qual, "external", sizeof (qual));
                        state = IS_REMOTE | IS_PASSIVE | IS_EXTERNAL;
                        if (metric == 0)
                                metric = 1;

                } else if (strcasecmp(qual, "active") == 0 ||
                    qual[0] == '\0') {

                        if (default_dst) {
                                msglog("bad net \"%s\" in "PATH_GATEWAYS
                                    " entry \"%s\"-- cannot be default",
                                    dname, lptr);
                                continue;
                        }

                        if (metric != 0) {
                                /*
                                 * Entries that are neither "passive" nor
                                 * "external" are "remote" and must behave
                                 * like physical interfaces.  If they are not
                                 * heard from regularly, they are deleted.
                                 */
                                state = IS_REMOTE;
                        } else {
                                /*
                                 * "remote" entries with a metric of 0
                                 * are aliases for our own interfaces
                                 */
                                state = IS_REMOTE | IS_PASSIVE | IS_ALIAS;
                        }

                } else {
                        msglog("bad "PATH_GATEWAYS" entry \"%s\";"
                            " unknown type %s", lptr, qual);
                        continue;
                }

                if (0 != (state & (IS_PASSIVE | IS_REMOTE)))
                        state |= IS_NO_RDISC;
                if (state & IS_PASSIVE)
                        state |= IS_NO_RIP;


                if (default_dst) {
                        addroutefordefault(dst, gate, netmask, metric,
                            ((state & IS_EXTERNAL)? RTS_EXTERNAL : 0));
                        continue;
                }

                ifp = check_dup(NULL, gate, dst, netmask, 0, _B_FALSE);
                if (ifp != NULL) {
                        msglog("duplicate "PATH_GATEWAYS" entry \"%s\"", lptr);
                        continue;
                }

                ifp = rtmalloc(sizeof (*ifp), "gwkludge()");
                (void) memset(ifp, 0, sizeof (*ifp));

                ifp->int_state = state;
                if (netmask == HOST_MASK)
                        ifp->int_if_flags = IFF_POINTOPOINT | IFF_UP;
                else
                        ifp->int_if_flags = IFF_UP;
                ifp->int_act_time = NEVER;
                ifp->int_addr = gate;
                ifp->int_dstaddr = dst;
                ifp->int_mask = netmask;
                ifp->int_ripv1_mask = netmask;
                ifp->int_std_mask = std_mask(gate);
                ifp->int_net = ntohl(dst);
                ifp->int_std_net = ifp->int_net & ifp->int_std_mask;
                ifp->int_std_addr = htonl(ifp->int_std_net);
                ifp->int_metric = metric;
                if (!(state & IS_EXTERNAL) &&
                    ifp->int_mask != ifp->int_std_mask)
                        ifp->int_state |= IS_SUBNET;
                (void) snprintf(ifp->int_name, sizeof (ifp->int_name),
                    "remote(%s)", gname);

                if_link(ifp, 0);
        }

        (void) fclose(fp);

        /*
         * After all of the parameter lines have been read,
         * apply them to any remote interfaces.
         */
        for (ifp = ifnet; NULL != ifp; ifp = ifp->int_next) {
                get_parms(ifp);

                tot_interfaces++;
                if (!IS_RIP_OFF(ifp->int_state))
                        rip_interfaces++;
                if (!IS_RIP_OUT_OFF(ifp->int_state))
                        ripout_interfaces++;

                trace_if("Add", ifp);
        }

}

/* Parse password timestamp */
static char *
parse_ts(time_t *tp,
    char **valp,
    char *val0,
    char *delimp,
    char *buf,
    uint_t bufsize)
{
        struct tm tm;

        if (0 > parse_quote(valp, "| ,", delimp, buf, bufsize) ||
            buf[bufsize-1] != '\0' || buf[bufsize-2] != '\0') {
                (void) snprintf(buf, bufsize, "bad timestamp %.25s", val0);
                return (buf);
        }
        (void) strlcat(buf, "\n", bufsize);
        (void) memset(&tm, 0, sizeof (tm));
        if (5 != sscanf(buf, "%u/%u/%u@%u:%u\n",
            (unsigned *)&tm.tm_year, (unsigned *)&tm.tm_mon,
            (unsigned *)&tm.tm_mday, (unsigned *)&tm.tm_hour,
            (unsigned *)&tm.tm_min) ||
            tm.tm_mon < 1 || tm.tm_mon > 12 ||
            tm.tm_mday < 1 || tm.tm_mday > 31) {
                (void) snprintf(buf, bufsize, "bad timestamp %.25s", val0);
                return (buf);
        }
        tm.tm_mon--;
        /* assume small years are in the 3rd millenium */
        if (tm.tm_year <= 37)
                tm.tm_year += 100;

        if (tm.tm_year >= 1900)
                tm.tm_year -= 1900;

        if ((*tp = mktime(&tm)) == -1) {
                (void) snprintf(buf, bufsize, "bad timestamp %.25s", val0);
                return (buf);
        }

        return (NULL);
}


/*
 * Get a password, key ID, and expiration date in the format
 *      passwd|keyID|year/mon/day@hour:min|year/mon/day@hour:min
 * returns NULL or error message
 */
static const char *
get_passwd(char *tgt,
    char *val,
    struct parm *parmp,
    uint16_t type,
    boolean_t safe)                     /* 1=from secure file */
{
        static char buf[80];
        char *val0, *p, delim;
        struct auth k, *ap, *ap2;
        int i;
        ulong_t l;


        if (!safe)
                return ("ignore unsafe password");

        for (ap = parmp->parm_auth, i = 0; ap->type != RIP_AUTH_NONE;
            i++, ap++) {
                if (i >= MAX_AUTH_KEYS)
                        return ("too many passwords");
        }

        (void) memset(&k, 0, sizeof (k));
        k.type = type;
        k.end = -1-DAY;

        val0 = val;
        if (0 > parse_quote(&val, "| ,", &delim,
            (char *)k.key, sizeof (k.key)))
                return (tgt);

        if (delim != '|') {
                if (type == RIP_AUTH_MD5)
                        return ("missing Keyid");
        } else {
                val0 = ++val;
                buf[sizeof (buf)-1] = '\0';
                if (0 > parse_quote(&val, "| ,", &delim, buf,
                    sizeof (buf)) ||
                    buf[sizeof (buf) - 1] != '\0' ||
                    (l = strtoul(buf, &p, 0)) > 255 ||
                    p == buf || *p != '\0') {
                        (void) snprintf(buf, sizeof (buf),
                            "bad KeyID \"%.20s\"", val0);
                        return (buf);
                }
                for (ap2 = parmp->parm_auth; ap2 < ap; ap2++) {
                        if (ap2->keyid == l) {
                                (void) snprintf(buf, sizeof (buf),
                                    "duplicate KeyID \"%.20s\"",
                                    val0);
                                return (buf);
                        }
                }
                k.keyid = (int)l;

                if (delim == '|') {
                        val0 = ++val;
                        if (NULL != (p = parse_ts(&k.start, &val, val0, &delim,
                            buf, sizeof (buf))))
                                return (p);
                        if (delim != '|')
                                return ("missing second timestamp");
                        val0 = ++val;
                        if (NULL != (p = parse_ts(&k.end, &val, val0, &delim,
                            buf, sizeof (buf))))
                                return (p);
                        if ((ulong_t)k.start > (ulong_t)k.end) {
                                (void) snprintf(buf, sizeof (buf),
                                    "out of order timestamp %.30s", val0);
                                return (buf);
                        }
                }
        }
        if (delim != '\0')
                return (tgt);

        (void) memmove(ap, &k, sizeof (*ap));
        return (NULL);
}


static const char *
bad_str(const char *estr)
{
        static char buf[100+8];

        (void) snprintf(buf, sizeof (buf), "bad \"%.100s\"", estr);
        return (buf);
}


/*
 * Parse a set of parameters for an interface.
 * returns NULL or error message
 */
const char *
parse_parms(char *line,
    boolean_t safe)                     /* 1=from secure file */
{
#define PARS(str) (strcasecmp(tgt, str) == 0)
#define PARSEQ(str) (strncasecmp(tgt, str"=", sizeof (str)) == 0)
/*
 * This macro checks for conflicting configurations options
 * For eg  one can set either the IS_NO_SOL_OUT flag bit or the IS_SOL_OUT flag
 * bit, but not both.
 */
#define CKF(g, b) {if (0 != (parm.parm_int_state & ((g) & ~(b)))) break; \
        parm.parm_int_state |= (b); }
        struct parm parm;
        struct intnet *intnetp;
        struct r1net *r1netp;
        struct tgate *tg;
        uint32_t addr, mask;
        char delim, *val0 = 0, *tgt, *val, *p;
        const char *msg;
        char buf[PARMS_MAXLINELEN], buf2[PARMS_MAXLINELEN];
        int i;


        /* "subnet=x.y.z.u/mask[,metric]" must be alone on the line */
        if (strncasecmp(line, "subnet=", sizeof ("subnet=") - 1) == 0 &&
            *(val = &line[sizeof ("subnet=") -1 ]) != '\0') {
                if (0 > parse_quote(&val, ",", &delim, buf, sizeof (buf)))
                        return (bad_str(line));
                intnetp = rtmalloc(sizeof (*intnetp),
                    "parse_parms subnet");
                intnetp->intnet_metric = 1;
                if (delim == ',') {
                        intnetp->intnet_metric = (int)strtol(val+1, &p, 0);
                        if (*p != '\0' || intnetp->intnet_metric <= 0 ||
                            val+1 == p ||
                            intnetp->intnet_metric >= HOPCNT_INFINITY) {
                                free(intnetp);
                                return (bad_str(line));
                        }
                }
                if (!getnet(buf, &intnetp->intnet_addr,
                    &intnetp->intnet_mask) ||
                    intnetp->intnet_mask == HOST_MASK ||
                    intnetp->intnet_addr == RIP_DEFAULT) {
                        free(intnetp);
                        return (bad_str(line));
                }
                intnetp->intnet_addr = htonl(intnetp->intnet_addr);
                intnetp->intnet_next = intnets;
                intnets = intnetp;
                return (NULL);
        }

        /*
         * "ripv1_mask=x.y.z.u/mask1,mask2" must be alone on the line.
         * This requires that x.y.z.u/mask1 be considered a subnet of
         * x.y.z.u/mask2, as if x.y.z.u/mask2 were a class-full network.
         */
        if (!strncasecmp(line, "ripv1_mask=", sizeof ("ripv1_mask=") - 1) &&
            *(val = &line[sizeof ("ripv1_mask=")-1]) != '\0') {
                if (0 > parse_quote(&val, ",", &delim, buf, sizeof (buf)) ||
                    delim == '\0')
                        return (bad_str(line));
                if ((i = (int)strtol(val+1, &p, 0)) <= 0 || i > 32 ||
                    *p != '\0')
                        return (bad_str(line));
                r1netp = rtmalloc(sizeof (*r1netp), "parse_parms ripv1_mask");
                r1netp->r1net_mask = HOST_MASK << (32-i);
                if (!getnet(buf, &r1netp->r1net_net, &r1netp->r1net_match) ||
                    r1netp->r1net_net == RIP_DEFAULT ||
                    r1netp->r1net_mask > r1netp->r1net_match) {
                        free(r1netp);
                        return (bad_str(line));
                }
                r1netp->r1net_next = r1nets;
                r1nets = r1netp;
                return (NULL);
        }

        (void) memset(&parm, 0, sizeof (parm));
        /*
         * Support of the following for Solaris backward compatibility
         * norip <ifname>
         * noripin <ifname>
         * noripout <ifname>
         */
        if (strncasecmp("norip", line, 5) == 0) {
                char cmd[64], ifname[64];
                int n;

                n = sscanf(line, "%63s %63s\n", cmd, ifname);
                if (n != 2) {
                        /* Not enough parameters */
                        return (bad_str(line));
                }

                /*
                 * Get the interface name and turn on the appropriate
                 * interface flags
                 */
                (void) strlcpy(parm.parm_name, ifname, sizeof (parm.parm_name));
                if (strcasecmp("norip", cmd) == 0) {
                        parm.parm_int_state |= IS_NO_RIP;
                } else if (strcasecmp("noripin", cmd) == 0) {
                        parm.parm_int_state |= IS_NO_RIP_IN;
                } else if (strcasecmp("noripout", cmd) == 0) {
                        parm.parm_int_state |= IS_NO_RIP_OUT;
                } else {
                        /* Bad command */
                        return (bad_str(line));
                }
                /*
                 * Look for duplication, and if new,
                 * link to the rest of the parm entries.
                 */
                return (insert_parm(&parm));
        }

        for (;;) {
                tgt = line + strspn(line, " ,\n\r");
                if (*tgt == '\0' || *tgt == '#')
                        break;
                line = tgt+strcspn(tgt, "= #,\n\r");
                delim = *line;
                if (delim == '=') {
                        val0 = ++line;
                        if (0 > parse_quote(&line, " #,", &delim,
                            buf, sizeof (buf)))
                                return (bad_str(tgt));
                }
                if (delim != '\0') {
                        for (;;) {
                                *line = '\0';
                                if (delim == '#')
                                        break;
                                ++line;
                                if (!isspace(delim) ||
                                    ((delim = *line), !isspace(delim)))
                                        break;
                        }
                }

                if (PARSEQ("if")) {
                        if (parm.parm_name[0] != '\0' ||
                            strlen(buf) > IF_NAME_LEN)
                                return (bad_str(tgt));
                        (void) strlcpy(parm.parm_name, buf,
                            sizeof (parm.parm_name));

                } else if (PARSEQ("addr")) {
                        /*
                         * This is a bad idea, because the address based
                         * sets of parameters cannot be checked for
                         * consistency with the interface name parameters.
                         * The parm_net stuff is needed to allow several
                         * -F settings.
                         */
                        if (!getnet(val0, &addr, &mask) ||
                            parm.parm_name[0] != '\0')
                                return (bad_str(tgt));
                        parm.parm_net = addr;
                        parm.parm_mask = mask;
                        parm.parm_name[0] = '\n';

                } else if (PARSEQ("passwd")) {
                        /*
                         * since cleartext passwords are so weak allow
                         * them anywhere
                         */
                        msg = get_passwd(tgt, val0, &parm, RIP_AUTH_PW, 1);
                        if (msg) {
                                *val0 = '\0';
                                return (bad_str(msg));
                        }

                } else if (PARSEQ("md5_passwd")) {
                        msg = get_passwd(tgt, val0, &parm, RIP_AUTH_MD5, safe);
                        if (msg) {
                                *val0 = '\0';
                                return (bad_str(msg));
                        }

                } else if (PARS("no_ag")) {
                        parm.parm_int_state |= (IS_NO_AG | IS_NO_SUPER_AG);

                } else if (PARS("no_host")) {
                        parm.parm_int_state |= IS_NO_HOST;

                } else if (PARS("no_super_ag")) {
                        parm.parm_int_state |= IS_NO_SUPER_AG;

                } else if (PARS("no_ripv1_in")) {
                        parm.parm_int_state |= IS_NO_RIPV1_IN;

                } else if (PARS("no_ripv2_in")) {
                        parm.parm_int_state |= IS_NO_RIPV2_IN;

                } else if (PARS("ripv2_out")) {
                        if (parm.parm_int_state & IS_NO_RIPV2_OUT)
                                return (bad_str(tgt));
                        parm.parm_int_state |= IS_NO_RIPV1_OUT;

                } else if (PARS("ripv2")) {
                        if ((parm.parm_int_state & IS_NO_RIPV2_OUT) ||
                            (parm.parm_int_state & IS_NO_RIPV2_IN))
                                return (bad_str(tgt));
                        parm.parm_int_state |= (IS_NO_RIPV1_IN
                            | IS_NO_RIPV1_OUT);

                } else if (PARS("no_rip")) {
                        CKF(IS_PM_RDISC, IS_NO_RIP);

                } else if (PARS("no_rip_mcast")) {
                        parm.parm_int_state |= IS_NO_RIP_MCAST;

                } else if (PARS("no_rdisc")) {
                        CKF((GROUP_IS_SOL_OUT|GROUP_IS_ADV_OUT), IS_NO_RDISC);

                } else if (PARS("no_solicit")) {
                        CKF(GROUP_IS_SOL_OUT, IS_NO_SOL_OUT);

                } else if (PARS("send_solicit")) {
                        CKF(GROUP_IS_SOL_OUT, IS_SOL_OUT);

                } else if (PARS("no_rdisc_adv")) {
                        CKF(GROUP_IS_ADV_OUT, IS_NO_ADV_OUT);

                } else if (PARS("rdisc_adv")) {
                        CKF(GROUP_IS_ADV_OUT, IS_ADV_OUT);

                } else if (PARS("bcast_rdisc")) {
                        parm.parm_int_state |= IS_BCAST_RDISC;

                } else if (PARS("passive")) {
                        CKF((GROUP_IS_SOL_OUT|GROUP_IS_ADV_OUT), IS_NO_RDISC);
                        parm.parm_int_state |= IS_NO_RIP | IS_PASSIVE;

                } else if (PARSEQ("rdisc_pref")) {
                        if (parm.parm_rdisc_pref != 0 ||
                            (parm.parm_rdisc_pref = (int)strtol(buf, &p, 0),
                            *p != '\0') || (buf == p))
                                return (bad_str(tgt));

                } else if (PARS("pm_rdisc")) {
                        if (IS_RIP_OUT_OFF(parm.parm_int_state))
                                return (bad_str(tgt));
                        parm.parm_int_state |= IS_PM_RDISC;

                } else if (PARSEQ("rdisc_interval")) {
                        if (parm.parm_rdisc_int != 0 ||
                            (parm.parm_rdisc_int = (int)strtoul(buf, &p, 0),
                            *p != '\0') || (buf == p) ||
                            parm.parm_rdisc_int < MIN_MAXADVERTISEINTERVAL ||
                            parm.parm_rdisc_int > MAX_MAXADVERTISEINTERVAL)
                                return (bad_str(tgt));

                } else if (PARSEQ("fake_default")) {
                        if (parm.parm_d_metric != 0 ||
                            IS_RIP_OUT_OFF(parm.parm_int_state) ||
                            (parm.parm_d_metric = (int)strtoul(buf, &p, 0),
                            *p != '\0') || (buf == p) ||
                            parm.parm_d_metric > HOPCNT_INFINITY-1)
                                return (bad_str(tgt));

                } else if (PARSEQ("trust_gateway")) {
                        /* look for trust_gateway=x.y.z|net/mask|...) */
                        p = buf;
                        if (0 > parse_quote(&p, "|", &delim, buf2,
                            sizeof (buf2)) || !gethost(buf2, &addr))
                                return (bad_str(tgt));
                        tg = rtmalloc(sizeof (*tg),
                            "parse_parms trust_gateway");
                        (void) memset(tg, 0, sizeof (*tg));
                        tg->tgate_addr = addr;
                        i = 0;
                        /* The default is to trust all routes. */
                        while (delim == '|') {
                                p++;
                                if (i >= MAX_TGATE_NETS ||
                                    0 > parse_quote(&p, "|", &delim, buf2,
                                    sizeof (buf2)) ||
                                    !getnet(buf2, &tg->tgate_nets[i].net,
                                    &tg->tgate_nets[i].mask) ||
                                    tg->tgate_nets[i].net == RIP_DEFAULT ||
                                    tg->tgate_nets[i].mask == 0) {
                                        free(tg);
                                        return (bad_str(tgt));
                                }
                                i++;
                        }
                        tg->tgate_next = tgates;
                        tgates = tg;
                        parm.parm_int_state |= IS_DISTRUST;

                } else if (PARS("redirect_ok")) {
                        parm.parm_int_state |= IS_REDIRECT_OK;

                } else if (PARSEQ("rip_neighbor")) {
                        if (parm.parm_name[0] == '\0' ||
                            gethost(buf, &parm.parm_ripout_addr) != 1)
                                return (bad_str(tgt));

                } else {
                        return (bad_str(tgt));  /* error */
                }
        }

        return (insert_parm(&parm));
#undef PARS
#undef PARSEQ
#undef CKF
}


/*
 * Insert parameter specifications into the parms list.  Returns NULL if
 * successful, or an error message otherwise.
 */
const char *
insert_parm(struct parm *new)
{
        struct parm *parmp, **parmpp;
        int i, num_passwds;

        /* set implicit values */
        if (new->parm_int_state & (IS_NO_ADV_IN|IS_NO_SOL_OUT))
                new->parm_int_state |= IS_NO_ADV_IN|IS_NO_SOL_OUT;

        for (i = num_passwds = 0; i < MAX_AUTH_KEYS; i++) {
                if (new->parm_auth[i].type != RIP_AUTH_NONE)
                        num_passwds++;
        }

        /* compare with existing sets of parameters */
        for (parmpp = &parms; (parmp = *parmpp) != 0;
            parmpp = &parmp->parm_next) {
                if (strcmp(new->parm_name, parmp->parm_name) != 0)
                        continue;
                if (!on_net(htonl(parmp->parm_net), new->parm_net,
                    new->parm_mask) &&
                    !on_net(htonl(new->parm_net), parmp->parm_net,
                    parmp->parm_mask))
                        continue;

                for (i = 0; i < MAX_AUTH_KEYS; i++) {
                        if (parmp->parm_auth[i].type != RIP_AUTH_NONE)
                                num_passwds++;
                }
                if (num_passwds > MAX_AUTH_KEYS)
                        return ("too many conflicting passwords");

                if ((0 != (new->parm_int_state & GROUP_IS_SOL_OUT) &&
                    0 != (parmp->parm_int_state & GROUP_IS_SOL_OUT) &&
                    0 != ((new->parm_int_state ^ parmp->parm_int_state) &&
                    GROUP_IS_SOL_OUT)) ||
                    (0 != (new->parm_int_state & GROUP_IS_ADV_OUT) &&
                    0 != (parmp->parm_int_state & GROUP_IS_ADV_OUT) &&
                    0 != ((new->parm_int_state ^ parmp->parm_int_state) &&
                    GROUP_IS_ADV_OUT)) ||
                    (new->parm_rdisc_pref != 0 &&
                    parmp->parm_rdisc_pref != 0 &&
                    new->parm_rdisc_pref != parmp->parm_rdisc_pref) ||
                    (new->parm_rdisc_int != 0 &&
                    parmp->parm_rdisc_int != 0 &&
                    new->parm_rdisc_int != parmp->parm_rdisc_int)) {
                        return ("conflicting, duplicate router discovery"
                            " parameters");

                }

                if (new->parm_d_metric != 0 && parmp->parm_d_metric != 0 &&
                    new->parm_d_metric != parmp->parm_d_metric) {
                        return ("conflicting, duplicate poor man's router"
                            " discovery or fake default metric");
                }
        }

        /*
         * link new entry on the list so that when the entries are scanned,
         * they affect the result in the order the operator specified.
         */
        parmp = rtmalloc(sizeof (*parmp), "insert_parm");
        (void) memcpy(parmp, new, sizeof (*parmp));
        *parmpp = parmp;

        return (NULL);
}

int                                     /* 0=bad */
gethost(char *name, in_addr_t *addrp)
{
        struct hostent *hp;
        struct in_addr in;


        /*
         * Try for a number first.  This avoids hitting the name
         * server which might be sick because routing is.
         */
        if ((in.s_addr = inet_addr(name)) != (in_addr_t)-1) {
                /*
                 * get a good number, but check that it makes some
                 * sense.
                 */
                if ((ntohl(in.s_addr) >> 24) == 0 ||
                    (ntohl(in.s_addr) >> 24) == 0xff)
                        return (0);
                *addrp = in.s_addr;
                return (1);
        }

        hp = gethostbyname(name);
        if (hp != NULL) {
                (void) memcpy(addrp, hp->h_addr, sizeof (*addrp));
                return (1);
        }

        return (0);
}


static void
addroutefordefault(in_addr_t dst, in_addr_t gate, in_addr_t mask,
    uint32_t metric, uint16_t rts_flags)
{
        struct rt_spare new;
        struct interface *ifp;
        uint16_t rt_newstate = RS_STATIC;


        ifp = iflookup(gate);
        if (ifp == NULL) {
                msglog("unreachable gateway %s in "PATH_GATEWAYS,
                    naddr_ntoa(gate));
                return;
        }

        trace_misc("addroutefordefault: found interface %s", ifp->int_name);

        (void) memset(&new, 0, sizeof (new));
        new.rts_ifp = ifp;
        new.rts_router = gate;
        new.rts_gate = gate;
        new.rts_metric = metric;
        new.rts_time = now.tv_sec;
        new.rts_flags = rts_flags;
        new.rts_origin = RO_FILE;

        input_route(dst, mask, &new, NULL, rt_newstate);
}