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mrouted

%{
/*
 * Configuration file parser for mrouted.
 *
 * Written by Bill Fenner, NRL, 1994
 *
 * cfparse.y,v 3.8.4.30 1998/03/01 01:48:58 fenner Exp
 */
#include <stdio.h>
#include <stdarg.h>
#include "defs.h"
#include <netdb.h>
#include <ifaddrs.h>

/*
 * Local function declarations
 */
static void		fatal(char *fmt, ...);
static void		warn(char *fmt, ...);
static void		yyerror(char *s);
static char *		next_word(void);
static int		yylex(void);
static u_int32		valid_if(char *s);
static const char *	ifconfaddr(u_int32_t a);
int			yyparse(void);

static FILE *f;

char *configfilename = _PATH_MROUTED_CONF;

extern int cache_lifetime;
extern int prune_lifetime;

int allow_black_holes = 0;

static int lineno;

static struct uvif *v;

static int order, state;
static int noflood = 0;
static int rexmit = VIFF_REXMIT_PRUNES;

struct addrmask {
	u_int32	addr;
	int	mask;
};

struct boundnam {
	char		*name;
	struct addrmask	 bound;
};

#define MAXBOUNDS 20

struct boundnam boundlist[MAXBOUNDS];	/* Max. of 20 named boundaries */
int numbounds = 0;			/* Number of named boundaries */

%}

%union
{
	int num;
	char *ptr;
	struct addrmask addrmask;
	u_int32 addr;
	struct vf_element *filterelem;
};

%token CACHE_LIFETIME PRUNE_LIFETIME PRUNING BLACK_HOLE NOFLOOD
%token PHYINT TUNNEL NAME
%token DISABLE IGMPV1 SRCRT BESIDE
%token METRIC THRESHOLD RATE_LIMIT BOUNDARY NETMASK ALTNET ADVERT_METRIC
%token FILTER ACCEPT DENY EXACT BIDIR REXMIT_PRUNES REXMIT_PRUNES2
%token PASSIVE ALLOW_NONPRUNERS
%token NOTRANSIT BLASTER FORCE_LEAF
%token PRUNE_LIFETIME2 NOFLOOD2
%token SYSNAM SYSCONTACT SYSVERSION SYSLOCATION
%token <num> BOOLEAN
%token <num> NUMBER
%token <ptr> STRING
%token <addrmask> ADDRMASK
%token <addr> ADDR

%type <addr> interface addrname
%type <addrmask> bound boundary addrmask
%type <filterelem> filter filtlist filtelement filtelem

%start conf

%%

conf	: stmts
	;

stmts	: /* Empty */
	| stmts stmt
	;

stmt	: error
	| PHYINT interface
	{
	    vifi_t vifi;

	    state++;

	    if (order)
		fatal("phyints must appear before tunnels");

	    for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
		if (!(v->uv_flags & VIFF_TUNNEL) && $2 == v->uv_lcl_addr)
		    break;
	    }

	    if (vifi == numvifs)
		fatal("%s is not a configured interface", inet_fmt($2, s1, sizeof(s1)));
	}
	ifmods
	| TUNNEL interface addrname
	{
	    const char *ifname;
	    struct ifreq ffr;
	    vifi_t vifi;

	    order++;

	    ifname = ifconfaddr($2);
	    if (ifname == 0)
		fatal("Tunnel local address %s is not mine", inet_fmt($2, s1, sizeof(s1)));

	    if (((ntohl($2) & IN_CLASSA_NET) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
		fatal("Tunnel local address %s is a loopback address", inet_fmt($2, s1, sizeof(s1)));

	    if (ifconfaddr($3) != NULL)
		fatal("Tunnel remote address %s is one of mine", inet_fmt($3, s1, sizeof(s1)));

	    for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
		if (v->uv_flags & VIFF_TUNNEL) {
		    if ($3 == v->uv_rmt_addr)
			fatal("Duplicate tunnel to %s",
			      inet_fmt($3, s1, sizeof(s1)));
		} else if (!(v->uv_flags & VIFF_DISABLED)) {
		    if (($3 & v->uv_subnetmask) == v->uv_subnet)
			fatal("Unnecessary tunnel to %s, same subnet as vif %d (%s)",
			      inet_fmt($3, s1, sizeof(s1)), vifi, v->uv_name);
		}
	    }

	    if (numvifs == MAXVIFS)
		fatal("too many vifs");

	    strlcpy(ffr.ifr_name, ifname, sizeof(ffr.ifr_name));
	    if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ffr)<0)
		fatal("ioctl SIOCGIFFLAGS on %s", ffr.ifr_name);

	    v = &uvifs[numvifs];
	    zero_vif(v, 1);
	    v->uv_flags	= VIFF_TUNNEL | rexmit | noflood;
	    v->uv_flags |= VIFF_OTUNNEL; /*XXX*/
	    v->uv_lcl_addr	= $2;
	    v->uv_rmt_addr	= $3;
	    v->uv_dst_addr	= $3;
	    strlcpy(v->uv_name, ffr.ifr_name, sizeof(v->uv_name));

	    if (!(ffr.ifr_flags & IFF_UP)) {
		v->uv_flags |= VIFF_DOWN;
		vifs_down = TRUE;
	    }
	}
	tunnelmods
	{
	    if (!(v->uv_flags & VIFF_OTUNNEL))
		init_ipip_on_vif(v);

	    logit(LOG_INFO, 0, "installing tunnel from %s to %s as vif #%u - rate=%d",
		  inet_fmt($2, s1, sizeof(s1)), inet_fmt($3, s2, sizeof(s2)),
		  numvifs, v->uv_rate_limit);

	    ++numvifs;

	}
	| CACHE_LIFETIME NUMBER
	{
	    if ($2 < MIN_CACHE_LIFETIME)
		warn("cache_lifetime %d must be at least %d", $2, MIN_CACHE_LIFETIME);
	    else
		cache_lifetime = $2;
	}
	| PRUNE_LIFETIME NUMBER
	{
	    if ($2 < MIN_PRUNE_LIFETIME)
		warn("prune_lifetime %d must be at least %d", $2, MIN_PRUNE_LIFETIME);
	    else
		prune_lifetime = $2;
	}
	| PRUNING BOOLEAN
	{
	    if ($2 != 1)
		warn("Disabling pruning is no longer supported");
	}
	| BLACK_HOLE
	{
#ifdef ALLOW_BLACK_HOLES
	    allow_black_holes = 1;
#endif
	}
	/*
	 * Turn off initial flooding (until subordinateness is learned
	 * via route exchange) on all phyints and set the default for
	 * all further tunnels.
	 */
	| NOFLOOD
	{
	    vifi_t vifi;

	    noflood = VIFF_NOFLOOD;
	    for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v)
		v->uv_flags |= VIFF_NOFLOOD;
	}
	/*
	 * Turn on prune retransmission on all interfaces.
	 * Tunnels default to retransmitting, so this just
	 * needs to turn on phyints.
	 */
	| REXMIT_PRUNES
	{
	    vifi_t vifi;

	    for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v)
		v->uv_flags |= VIFF_REXMIT_PRUNES;
	}
	/*
	 * If true, do as above.  If false, no need to turn
	 * it off for phyints since they default to not
	 * rexmit; need to set flag to not rexmit on tunnels.
	 */
	| REXMIT_PRUNES BOOLEAN
	{
	    if ($2) {
		vifi_t vifi;

		for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v)
		    v->uv_flags |= VIFF_REXMIT_PRUNES;
	    } else {
		rexmit = 0;
	    }
	}
	| NAME STRING boundary
	{
	    size_t len = strlen($2) + 1;
	    if (numbounds >= MAXBOUNDS) {
		fatal("Too many named boundaries (max %d)", MAXBOUNDS);
	    }

	    boundlist[numbounds].name = malloc(len);
	    strlcpy(boundlist[numbounds].name, $2, len);
	    boundlist[numbounds++].bound = $3;
	}
	| SYSNAM STRING
	{
#ifdef SNMP
	    set_sysName($2);
#endif /* SNMP */
	}
	| SYSCONTACT STRING
	{
#ifdef SNMP
	    set_sysContact($2);
#endif /* SNMP */
	}
        | SYSVERSION STRING
	{
#ifdef SNMP
	    set_sysVersion($2);
#endif /* SNMP */
	}
	| SYSLOCATION STRING
	{
#ifdef SNMP
	    set_sysLocation($2);
#endif /* SNMP */
	}
	;

tunnelmods	: /* empty */
	| tunnelmods tunnelmod
	;

tunnelmod	: mod
	| BESIDE
	{
	    v->uv_flags |= VIFF_OTUNNEL;
	}
	| BESIDE BOOLEAN
	{
	    if ($2)
		v->uv_flags |= VIFF_OTUNNEL;
	    else
		v->uv_flags &= ~VIFF_OTUNNEL;
	}
	| SRCRT
	{
	    fatal("Source-route tunnels not supported");
	}
	;

ifmods	: /* empty */
	| ifmods ifmod
	;

ifmod	: mod
	| DISABLE		{ v->uv_flags |= VIFF_DISABLED; }
	| IGMPV1		{ v->uv_flags |= VIFF_IGMPV1; }
	| NETMASK addrname
	{
	    u_int32 subnet, mask;

	    mask = $2;
	    subnet = v->uv_lcl_addr & mask;
	    if (!inet_valid_subnet(subnet, mask))
		fatal("Invalid netmask");
	    v->uv_subnet = subnet;
	    v->uv_subnetmask = mask;
	    v->uv_subnetbcast = subnet | ~mask;
	}
	| NETMASK
	{
	    warn("Expected address after netmask keyword, ignored");
	}
	| ALTNET addrmask
	{
	    struct phaddr *ph;

	    ph = (struct phaddr *)malloc(sizeof(struct phaddr));
	    if (ph == NULL)
		fatal("out of memory");

	    if ($2.mask) {
		VAL_TO_MASK(ph->pa_subnetmask, $2.mask);
	    } else {
		ph->pa_subnetmask = v->uv_subnetmask;
	    }

	    ph->pa_subnet = $2.addr & ph->pa_subnetmask;
	    ph->pa_subnetbcast = ph->pa_subnet | ~ph->pa_subnetmask;

	    if ($2.addr & ~ph->pa_subnetmask)
		warn("Extra subnet %s/%d has host bits set",
		     inet_fmt($2.addr, s1, sizeof(s1)), $2.mask);

	    ph->pa_next = v->uv_addrs;
	    v->uv_addrs = ph;
	}
	| ALTNET
	{
	    warn("Expected address after altnet keyword, ignored");
	}
	| FORCE_LEAF
	{
	    v->uv_flags |= VIFF_FORCE_LEAF;
	}
	| FORCE_LEAF BOOLEAN
	{
	    if ($2)
		v->uv_flags |= VIFF_FORCE_LEAF;
	    else
		v->uv_flags &= ~VIFF_FORCE_LEAF;
	}
	;

mod	: THRESHOLD NUMBER
	{
	    if ($2 < 1 || $2 > 255)
		fatal("Invalid threshold %d",$2);
	    v->uv_threshold = $2;
	}
	| THRESHOLD
	{
	    warn("Expected number after threshold keyword, ignored");
	}
	| METRIC NUMBER
	{
	    if ($2 < 1 || $2 > UNREACHABLE)
		fatal("Invalid metric %d",$2);
	    v->uv_metric = $2;
	}
	| METRIC
	{
	    warn("Expected number after metric keyword, ignored");
	}
	| ADVERT_METRIC NUMBER
	{
	    if ($2 < 0 || $2 > UNREACHABLE - 1)
		fatal("Invalid advert_metric %d", $2);
	    v->uv_admetric = $2;
	}
	| ADVERT_METRIC
	{
	    warn("Expected number after advert_metric keyword, ignored");
	}
	| RATE_LIMIT NUMBER
	{
	    if ($2 > MAX_RATE_LIMIT)
		fatal("Invalid rate_limit %d",$2);
	    v->uv_rate_limit = $2;
	}
	| RATE_LIMIT
	{
	    warn("Expected number after rate_limit keyword, ignored");
	}
	| BOUNDARY bound
	{
	    struct vif_acl *v_acl;

	    v_acl = (struct vif_acl *)malloc(sizeof(struct vif_acl));
	    if (v_acl == NULL)
		fatal("out of memory");

	    VAL_TO_MASK(v_acl->acl_mask, $2.mask);
	    v_acl->acl_addr = $2.addr & v_acl->acl_mask;
	    if ($2.addr & ~v_acl->acl_mask)
		warn("Boundary spec %s/%d has host bits set",
		     inet_fmt($2.addr, s1, sizeof(s1)), $2.mask);
	    v_acl->acl_next = v->uv_acl;
	    v->uv_acl = v_acl;
	}
	| BOUNDARY
	{
	    warn("Expected boundary spec after boundary keyword, ignored");
	}
	| REXMIT_PRUNES2
	{
	    v->uv_flags |= VIFF_REXMIT_PRUNES;
	}
	| REXMIT_PRUNES2 BOOLEAN
	{
	    if ($2)
		v->uv_flags |= VIFF_REXMIT_PRUNES;
	    else
		v->uv_flags &= ~VIFF_REXMIT_PRUNES;
	}
	| PASSIVE
	{
	    v->uv_flags |= VIFF_PASSIVE;
	}
	| NOFLOOD2
	{
	    v->uv_flags |= VIFF_NOFLOOD;
	}
	| NOTRANSIT
	{
	    v->uv_flags |= VIFF_NOTRANSIT;
	}
	| BLASTER
	{
	    v->uv_flags |= VIFF_BLASTER;
	    blaster_alloc(v - uvifs);
	}
	| ALLOW_NONPRUNERS
	{
		    v->uv_flags |= VIFF_ALLOW_NONPRUNERS;
	}
	| PRUNE_LIFETIME2 NUMBER
	{
	    if ($2 < MIN_PRUNE_LIFETIME)
		warn("prune_lifetime %d must be at least %d", $2, MIN_PRUNE_LIFETIME);
	    else
		v->uv_prune_lifetime = $2;
	}
	| ACCEPT filter
	{
	    if (v->uv_filter == NULL) {
		struct vif_filter *v_filter;

		v_filter = (struct vif_filter *)malloc(sizeof(struct vif_filter));
		if (v_filter == NULL)
		    fatal("out of memory");

		v_filter->vf_flags = 0;
		v_filter->vf_type = VFT_ACCEPT;
		v_filter->vf_filter = $2;
		v->uv_filter = v_filter;
	    } else if (v->uv_filter->vf_type != VFT_ACCEPT) {
		fatal("Cannot accept and deny");
	    } else {
		struct vf_element *p;

		p = v->uv_filter->vf_filter;
		while (p->vfe_next)
		    p = p->vfe_next;
		p->vfe_next = $2;
	    }
	}
	| ACCEPT
	{
	    warn("Expected filter spec after accept keyword, ignored");
	}
	| DENY filter
	{
	    if (v->uv_filter == NULL) {
		struct vif_filter *v_filter;

		v_filter = (struct vif_filter *)malloc(sizeof(struct vif_filter));
		if (v_filter == NULL)
		    fatal("out of memory");

		v_filter->vf_flags = 0;
		v_filter->vf_type = VFT_DENY;
		v_filter->vf_filter = $2;
		v->uv_filter = v_filter;
	    } else if (v->uv_filter->vf_type != VFT_DENY) {
		fatal("Cannot accept and deny");
	    } else {
		struct vf_element *p;

		p = v->uv_filter->vf_filter;
		while (p->vfe_next)
		    p = p->vfe_next;
		p->vfe_next = $2;
	    }
	}
	| DENY
	{
		warn("Expected filter spec after deny keyword, ignored");
	}
	| BIDIR
	{
	    if (v->uv_filter == NULL)
		fatal("bidir goes after filters");
	    v->uv_filter->vf_flags |= VFF_BIDIR;
	}
	;

interface: ADDR
	{
	    $$ = $1;
	}
	| STRING
	{
	    $$ = valid_if($1);
	    if ($$ == 0)
		fatal("Invalid interface name %s",$1);
	}
	;

addrname: ADDR
	{
	    $$ = $1;
	}
	| STRING
	{
	    struct hostent *hp;

	    if ((hp = gethostbyname($1)) == NULL || hp->h_length != sizeof($$))
		fatal("No such host %s", $1);

	    if (hp->h_addr_list[1])
		fatal("Hostname %s does not %s", $1, "map to a unique address");

	    memmove (&$$, hp->h_addr_list[0], hp->h_length);
	}

bound	: boundary
	{
	    $$ = $1;
	}
	| STRING
	{
	    int i;

	    for (i=0; i < numbounds; i++) {
		if (!strcmp(boundlist[i].name, $1)) {
		    $$ = boundlist[i].bound;
		    break;
		}
	    }

	    if (i == numbounds)
		fatal("Invalid boundary name %s",$1);
	}
	;

boundary: ADDRMASK
	{
#ifdef ALLOW_BLACK_HOLES
	    if (!allow_black_holes)
#endif
		if ((ntohl($1.addr) & 0xff000000) != 0xef000000) {
		    fatal("Boundaries must be 239.x.x.x, not %s/%d",
			  inet_fmt($1.addr, s1, sizeof(s1)), $1.mask);
		}
	    $$ = $1;
	}
	;

addrmask: ADDRMASK		{ $$ = $1; }
	| ADDR			{ $$.addr = $1; $$.mask = 0; }
	;

filter	: filtlist		{ $$ = $1; }
	| STRING		{ fatal("named filters no implemented yet"); }
	;

filtlist : filtelement		{ $$ = $1; }
	| filtelement filtlist	{ $1->vfe_next = $2; $$ = $1; }
	;

filtelement : filtelem		{ $$ = $1; }
	| filtelem EXACT	{ $1->vfe_flags |= VFEF_EXACT; $$ = $1; }
	;

filtelem : ADDRMASK
	{
	    struct vf_element *vfe;

	    vfe = (struct vf_element *)malloc(sizeof(struct vf_element));
	    if (vfe == NULL)
		fatal("out of memory");

	    vfe->vfe_addr = $1.addr;
	    VAL_TO_MASK(vfe->vfe_mask, $1.mask);
	    vfe->vfe_flags = 0;
	    vfe->vfe_next = NULL;

	    $$ = vfe;
	}
%%
static void fatal(char *fmt, ...)
{
	va_list ap;
	char buf[MAXHOSTNAMELEN + 100];

	va_start(ap, fmt);
	vsnprintf(buf, sizeof(buf), fmt, ap);
	va_end(ap);

	logit(LOG_ERR, 0, "%s: %s near line %d", configfilename, buf, lineno);
}

static void warn(char *fmt, ...)
{
    va_list ap;
    char buf[200];

    va_start(ap, fmt);
    vsnprintf(buf, sizeof(buf), fmt, ap);
    va_end(ap);

    logit(LOG_WARNING, 0, "%s: %s near line %d", configfilename, buf, lineno);
}

static void yyerror(char *s)
{
    logit(LOG_ERR, 0, "%s: %s near line %d", configfilename, s, lineno);
}

static char *next_word(void)
{
    static char buf[1024];
    static char *p=NULL;
    char *q;

    while (1) {
        if (!p || !*p) {
            lineno++;
            if (fgets(buf, sizeof(buf), f) == NULL)
                return NULL;
            p = buf;
        }
        while (*p && (*p == ' ' || *p == '\t'))	/* skip whitespace */
            p++;
        if (*p == '#') {
            p = NULL;		/* skip comments */
            continue;
        }
        q = p;
#ifdef SNMP
        if (*p == '"') {
            p++;
            while (*p && *p != '"' && *p != '\n')
                p++;		/* find next whitespace */
            if (*p == '"')
                p++;
        } else
#endif
        while (*p && *p != ' ' && *p != '\t' && *p != '\n')
            p++;		/* find next whitespace */
        *p++ = '\0';	/* null-terminate string */

        if (!*q) {
            p = NULL;
            continue;	/* if 0-length string, read another line */
        }

        return q;
    }
}

/*
 * List of keywords.  Must have an empty record at the end to terminate
 * list.  If a second value is specified, the first is used at the beginning
 * of the file and the second is used while parsing interfaces (e.g. after
 * the first "phyint" or "tunnel" keyword).
 */
static struct keyword {
	char	*word;
	int	val1;
	int	val2;
} words[] = {
	{ "cache_lifetime",	CACHE_LIFETIME, 0 },
	{ "prune_lifetime",	PRUNE_LIFETIME,	PRUNE_LIFETIME2 },
	{ "pruning",		PRUNING, 0 },
	{ "phyint",		PHYINT, 0 },
	{ "tunnel",		TUNNEL, 0 },
	{ "disable",		DISABLE, 0 },
	{ "metric",		METRIC, 0 },
	{ "advert_metric",	ADVERT_METRIC, 0 },
	{ "threshold",		THRESHOLD, 0 },
	{ "rate_limit",		RATE_LIMIT, 0 },
	{ "force_leaf",		FORCE_LEAF, 0 },
	{ "srcrt",		SRCRT, 0 },
	{ "sourceroute",	SRCRT, 0 },
	{ "boundary",		BOUNDARY, 0 },
	{ "netmask",		NETMASK, 0 },
	{ "igmpv1",		IGMPV1, 0 },
	{ "altnet",		ALTNET, 0 },
	{ "name",		NAME, 0 },
	{ "accept",		ACCEPT, 0 },
	{ "deny",		DENY, 0 },
	{ "exact",		EXACT, 0 },
	{ "bidir",		BIDIR, 0 },
	{ "allow_nonpruners",	ALLOW_NONPRUNERS, 0 },
#ifdef ALLOW_BLACK_HOLES
	{ "allow_black_holes",	BLACK_HOLE, 0 },
#endif
	{ "noflood",		NOFLOOD, NOFLOOD2 },
	{ "notransit",		NOTRANSIT, 0 },
	{ "blaster",		BLASTER, 0 },
	{ "rexmit_prunes",	REXMIT_PRUNES, REXMIT_PRUNES2 },
	{ "passive",		PASSIVE, 0 },
	{ "beside",		BESIDE, 0 },
#ifdef SNMP
	{ "sysName",		SYSNAM, 0 },
	{ "sysContact",		SYSCONTACT, 0 },
	{ "sysVersion",		SYSVERSION, 0 },
	{ "sysLocation",	SYSLOCATION, 0 },
#endif
	{ NULL,			0, 0 }
};


static int yylex(void)
{
    u_int32 addr, n;
    char *q;
    struct keyword *w;

    if ((q = next_word()) == NULL) {
        return 0;
    }

    for (w = words; w->word; w++)
        if (!strcmp(q, w->word))
            return (state && w->val2) ? w->val2 : w->val1;

    if (!strcmp(q,"on") || !strcmp(q,"yes")) {
        yylval.num = 1;
        return BOOLEAN;
    }
    if (!strcmp(q,"off") || !strcmp(q,"no")) {
        yylval.num = 0;
        return BOOLEAN;
    }
    if (!strcmp(q,"default")) {
        yylval.addrmask.mask = 0;
        yylval.addrmask.addr = 0;
        return ADDRMASK;
    }
    if (sscanf(q,"%[.0-9]/%u%c",s1,&n,s2) == 2) {
        if ((addr = inet_parse(s1,1)) != 0xffffffff) {
            yylval.addrmask.mask = n;
            yylval.addrmask.addr = addr;
            return ADDRMASK;
        }
        /* fall through to returning STRING */
    }
    if (sscanf(q,"%[.0-9]%c",s1,s2) == 1) {
        if ((addr = inet_parse(s1,4)) != 0xffffffff &&
            inet_valid_host(addr)) { 
            yylval.addr = addr;
            return ADDR;
        }
    }
    if (sscanf(q,"0x%8x%c", &n, s1) == 1) {
        yylval.addr = n;
        return ADDR;
    }
    if (sscanf(q,"%u%c",&n,s1) == 1) {
        yylval.num = n;
        return NUMBER;
    }
#ifdef SNMP
    if (*q=='"') {
        if (q[ strlen(q)-1 ]=='"')
            q[ strlen(q)-1 ]='\0'; /* trash trailing quote */
        yylval.ptr = q+1;
        return STRING;
    }
#endif
    yylval.ptr = q;
    return STRING;
}

void config_vifs_from_file(void)
{
    order = 0;
    state = 0;
    numbounds = 0;
    lineno = 0;

    if ((f = fopen(configfilename, "r")) == NULL) {
        if (errno != ENOENT)
            logit(LOG_ERR, errno, "Cannot open %s", configfilename);
        return;
    }

    yyparse();

    fclose(f);
}

static u_int32 valid_if(char *s)
{
    vifi_t vifi;
    struct uvif *v;

    for (vifi=0, v=uvifs; vifi<numvifs; vifi++, v++) {
        if (!strcmp(v->uv_name, s))
            return v->uv_lcl_addr;
    }

    return 0;
}

static const char *ifconfaddr(u_int32_t a)
{
    static char ifname[IFNAMSIZ];
    struct ifaddrs *ifap, *ifa;

    if (getifaddrs(&ifap) != 0)
	return NULL;

    for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
	if (ifa->ifa_addr &&
	    ifa->ifa_addr->sa_family == AF_INET &&
	    ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr == a) {
	    strlcpy(ifname, ifa->ifa_name, sizeof(ifname));
	    freeifaddrs(ifap);

	    return ifname;
	}
    }

    freeifaddrs(ifap);

    return NULL;
}

/**
 * Local Variables:
 *  version-control: t
 *  indent-tabs-mode: t
 *  c-file-style: "ellemtel"
 *  c-basic-offset: 4
 * End:
 */