res_init.c

KPIT GNU Tools is a set of GNU development tools for Renesas microcontrollers.

				    n = 0;
			    }
		    }
		    /* null terminate last domain if there are excess */
		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
			    cp++;
		    *cp = '\0';
		    *pp++ = 0;
		    havesearch = 1;
		    continue;
		}
		/* read nameservers to query */
		if (MATCH(buf, "nameserver") && nserv < MAXNS) {
		    char *q;
		    struct addrinfo hints, *res;
		    char pbuf[NI_MAXSERV];

		    cp = buf + sizeof("nameserver") - 1;
		    while (*cp == ' ' || *cp == '\t')
			cp++;
		    if ((*cp == '\0') || (*cp == '\n'))
			continue;
		    for (q = cp; *q; q++) {
			if (isspace(*q)) {
			    *q = '\0';
			    break;
			}
		    }
		    memset(&hints, 0, sizeof(hints));
		    hints.ai_flags = AI_NUMERICHOST;
		    hints.ai_socktype = SOCK_DGRAM;
		    snprintf(pbuf, sizeof(pbuf), "%d", NAMESERVER_PORT);
		    if (getaddrinfo(cp, pbuf, &hints, &res) == 0 &&
			    res->ai_next == NULL) {
			if (res->ai_addrlen <= sizeof(_res_ext.nsaddr_list[nserv])) {
			    memcpy(&_res_ext.nsaddr_list[nserv], res->ai_addr,
				res->ai_addrlen);
			} else {
			    memset(&_res_ext.nsaddr_list[nserv], 0,
				sizeof(_res_ext.nsaddr_list[nserv]));
			}
			if (res->ai_addrlen <= sizeof(_res.nsaddr_list[nserv])) {
			    memcpy(&_res.nsaddr_list[nserv], res->ai_addr,
				res->ai_addrlen);
			} else {
			    memset(&_res.nsaddr_list[nserv], 0,
				sizeof(_res.nsaddr_list[nserv]));
			}
			nserv++;
		    }
		    if (res)
			    freeaddrinfo(res);
		    continue;
		}
#ifdef RESOLVSORT
		if (MATCH(buf, "sortlist")) {
		    struct in_addr a;
		    struct in6_addr a6;
		    int m, i;
		    u_char *u;

		    cp = buf + sizeof("sortlist") - 1;
		    while (nsort < MAXRESOLVSORT) {
			while (*cp == ' ' || *cp == '\t')
			    cp++;
			if (*cp == '\0' || *cp == '\n' || *cp == ';')
			    break;
			net = cp;
			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
			       isascii(*cp) && !isspace(*cp))
				cp++;
			n = *cp;
			*cp = 0;
			if (inet_aton(net, &a)) {
			    _res.sort_list[nsort].addr = a;
			    if (ISSORTMASK(n)) {
				*cp++ = n;
				net = cp;
				while (*cp && *cp != ';' &&
					isascii(*cp) && !isspace(*cp))
				    cp++;
				n = *cp;
				*cp = 0;
				if (inet_aton(net, &a)) {
				    _res.sort_list[nsort].mask = a.s_addr;
				} else {
				    _res.sort_list[nsort].mask = 
					net_mask(_res.sort_list[nsort].addr);
				}
			    } else {
				_res.sort_list[nsort].mask = 
				    net_mask(_res.sort_list[nsort].addr);
			    }
			    _res_ext.sort_list[nsort].af = AF_INET;
			    _res_ext.sort_list[nsort].addr.ina =
				_res.sort_list[nsort].addr;
			    _res_ext.sort_list[nsort].mask.ina.s_addr =
				_res.sort_list[nsort].mask;
			    nsort++;
			}
			else if (inet_pton(AF_INET6, net, &a6) == 1) {

			    _res_ext.sort_list[nsort].af = AF_INET6;
			    _res_ext.sort_list[nsort].addr.in6a = a6;
			    u = (u_char *)&_res_ext.sort_list[nsort].mask.in6a;
			    *cp++ = n;
			    net = cp;
			    while (*cp && *cp != ';' &&
				    isascii(*cp) && !isspace(*cp))
				cp++;
			    m = n;
			    n = *cp;
			    *cp = 0;
			    switch (m) {
			    case '/':
				m = atoi(net);
				break;
			    case '&':
				if (inet_pton(AF_INET6, net, u) == 1) {
				    m = -1;
				    break;
				}
				/*FALLTHROUGH*/
			    default:
				m = sizeof(struct in6_addr) * NBBY;
				break;
			    }
			    if (m >= 0) {
				for (i = 0; i < sizeof(struct in6_addr); i++) {
				    if (m <= 0) {
					*u = 0;
				    } else {
					m -= NBBY;
					*u = (u_char)~0;
					if (m < 0)
					    *u <<= -m;
				    }
				    u++;
				}
			    }
			    _res.sort_list[nsort].addr.s_addr =
				(u_int32_t)0xffffffff;
			    _res.sort_list[nsort].mask = (u_int32_t)0xffffffff;
			    nsort++;
			}
			*cp = n;
		    }
		    continue;
		}
#endif
		if (MATCH(buf, "options")) {
		    res_setoptions(buf + sizeof("options") - 1, "conf");
		    continue;
		}
	    }
	    if (nserv > 1) 
		_res.nscount = nserv;
#ifdef RESOLVSORT
	    _res.nsort = nsort;
#endif
	    (void) fclose(fp);
	}
	if (_res.defdname[0] == 0 &&
	    gethostname(buf, sizeof(_res.defdname) - 1) == 0 &&
	    (cp = strchr(buf, '.')) != NULL)
		strcpy(_res.defdname, cp + 1);

	/* find components of local domain that might be searched */
	if (havesearch == 0) {
		pp = _res.dnsrch;
		*pp++ = _res.defdname;
		*pp = NULL;

#ifndef RFC1535
		dots = 0;
		for (cp = _res.defdname; *cp; cp++)
			dots += (*cp == '.');

		cp = _res.defdname;
		while (pp < _res.dnsrch + MAXDFLSRCH) {
			if (dots < LOCALDOMAINPARTS)
				break;
			cp = strchr(cp, '.') + 1;    /* we know there is one */
			*pp++ = cp;
			dots--;
		}
		*pp = NULL;
#ifdef DEBUG
		if (_res.options & RES_DEBUG) {
			printf(";; res_init()... default dnsrch list:\n");
			for (pp = _res.dnsrch; *pp; pp++)
				printf(";;\t%s\n", *pp);
			printf(";;\t..END..\n");
		}
#endif
#endif /* !RFC1535 */
	}

	if (issetugid())
		_res.options |= RES_NOALIASES;
	else if ((cp = getenv("RES_OPTIONS")) != NULL)
		res_setoptions(cp, "env");
	_res.options |= RES_INIT;
	return (0);
}

static void
res_setoptions(options, source)
	char *options, *source;
{
	char *cp = options;
	int i;

#ifdef DEBUG
	if (_res.options & RES_DEBUG)
		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
		       options, source);
#endif
	while (*cp) {
		/* skip leading and inner runs of spaces */
		while (*cp == ' ' || *cp == '\t')
			cp++;
		/* search for and process individual options */
		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
			i = atoi(cp + sizeof("ndots:") - 1);
			if (i <= RES_MAXNDOTS)
				_res.ndots = i;
			else
				_res.ndots = RES_MAXNDOTS;
#ifdef DEBUG
			if (_res.options & RES_DEBUG)
				printf(";;\tndots=%d\n", _res.ndots);
#endif
		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
#ifdef DEBUG
			if (!(_res.options & RES_DEBUG)) {
				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
				       options, source);
				_res.options |= RES_DEBUG;
			}
			printf(";;\tdebug\n");
#endif
		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
			_res.options |= RES_USE_INET6;
		} else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) {
		       _res.options |= RES_INSECURE1;
		} else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) {
		       _res.options |= RES_INSECURE2;
		} else if (!strncmp(cp, "no_tld_query", sizeof("no_tld_query") - 1)) {
			_res.options |= RES_NOTLDQUERY;
		} else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
		       _res.options |= RES_USE_EDNS0;
		} else {
			/* XXX - print a warning here? */
		}
		/* skip to next run of spaces */
		while (*cp && *cp != ' ' && *cp != '\t')
			cp++;
	}
}

#ifdef RESOLVSORT
/* XXX - should really support CIDR which means explicit masks always. */
static u_int32_t
net_mask(in)		/* XXX - should really use system's version of this */
	struct in_addr in;
{
	u_int32_t i = ntohl(in.s_addr);

	if (IN_CLASSA(i))
		return (htonl(IN_CLASSA_NET));
	else if (IN_CLASSB(i))
		return (htonl(IN_CLASSB_NET));
	return (htonl(IN_CLASSC_NET));
}
#endif

u_int
res_randomid()
{
	struct timeval now;

	gettimeofday(&now, NULL);
	return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
}

/*
 * Weak aliases for applications that use certain private entry points,
 * and fail to include <resolv.h>.
 */
#undef res_init
__weak_reference(__res_init, res_init);