dighost.c

来自「非常好的dns解析软件」· C语言 代码 · 共 2,368 行 · 第 1/5 页

		 */
		char *p = reverse;
		char *end = reverse + len;
		if (strict && inet_pton(AF_INET, value, &addr.type.in) != 1)
			return (DNS_R_BADDOTTEDQUAD);
		result = reverse_octets(value, &p, end);
		if (result != ISC_R_SUCCESS)
			return (result);
		/* Append .in-addr.arpa. and a terminating NUL. */
		result = append(".in-addr.arpa.", 15, &p, end);
		if (result != ISC_R_SUCCESS)
			return (result);
		return (ISC_R_SUCCESS);
	}
}

void
fatal(const char *format, ...) {
	va_list args;

	fprintf(stderr, "%s: ", progname);
	va_start(args, format);
	vfprintf(stderr, format, args);
	va_end(args);
	fprintf(stderr, "\n");
	if (exitcode < 10)
		exitcode = 10;
	if (fatalexit != 0)
		exitcode = fatalexit;
	exit(exitcode);
}

void
debug(const char *format, ...) {
	va_list args;

	if (debugging) {
		va_start(args, format);
		vfprintf(stderr, format, args);
		va_end(args);
		fprintf(stderr, "\n");
	}
}

void
check_result(isc_result_t result, const char *msg) {
	if (result != ISC_R_SUCCESS) {
		fatal("%s: %s", msg, isc_result_totext(result));
	}
}

/*%
 * Create a server structure, which is part of the lookup structure.
 * This is little more than a linked list of servers to query in hopes
 * of finding the answer the user is looking for
 */
dig_server_t *
make_server(const char *servname, const char *userarg) {
	dig_server_t *srv;

	REQUIRE(servname != NULL);

	debug("make_server(%s)", servname);
	srv = isc_mem_allocate(mctx, sizeof(struct dig_server));
	if (srv == NULL)
		fatal("memory allocation failure in %s:%d",
		      __FILE__, __LINE__);
	strncpy(srv->servername, servname, MXNAME);
	strncpy(srv->userarg, userarg, MXNAME);
	srv->servername[MXNAME-1] = 0;
	srv->userarg[MXNAME-1] = 0;
	ISC_LINK_INIT(srv, link);
	return (srv);
}

static int
addr2af(int lwresaddrtype)
{
	int af = 0;

	switch (lwresaddrtype) {
	case LWRES_ADDRTYPE_V4:
		af = AF_INET;
		break;

	case LWRES_ADDRTYPE_V6:
		af = AF_INET6;
		break;
	}

	return (af);
}

/*%
 * Create a copy of the server list from the lwres configuration structure.
 * The dest list must have already had ISC_LIST_INIT applied.
 */
static void
copy_server_list(lwres_conf_t *confdata, dig_serverlist_t *dest) {
	dig_server_t *newsrv;
	char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")];
	int af;
	int i;

	debug("copy_server_list()");
	for (i = 0; i < confdata->nsnext; i++) {
		af = addr2af(confdata->nameservers[i].family);

		lwres_net_ntop(af, confdata->nameservers[i].address,
				   tmp, sizeof(tmp));
		newsrv = make_server(tmp, tmp);
		ISC_LINK_INIT(newsrv, link);
		ISC_LIST_ENQUEUE(*dest, newsrv, link);
	}
}

void
flush_server_list(void) {
	dig_server_t *s, *ps;

	debug("flush_server_list()");
	s = ISC_LIST_HEAD(server_list);
	while (s != NULL) {
		ps = s;
		s = ISC_LIST_NEXT(s, link);
		ISC_LIST_DEQUEUE(server_list, ps, link);
		isc_mem_free(mctx, ps);
	}
}

void
set_nameserver(char *opt) {
	isc_result_t result;
	isc_sockaddr_t sockaddrs[DIG_MAX_ADDRESSES];
	isc_netaddr_t netaddr;
	int count, i;
	dig_server_t *srv;
	char tmp[ISC_NETADDR_FORMATSIZE];

	if (opt == NULL)
		return;

	result = bind9_getaddresses(opt, 0, sockaddrs,
				    DIG_MAX_ADDRESSES, &count); 
	if (result != ISC_R_SUCCESS)
		fatal("couldn't get address for '%s': %s",
		      opt, isc_result_totext(result));

	flush_server_list();
	
	for (i = 0; i < count; i++) {
		isc_netaddr_fromsockaddr(&netaddr, &sockaddrs[i]);
		isc_netaddr_format(&netaddr, tmp, sizeof(tmp));
		srv = make_server(tmp, opt);
		if (srv == NULL)
			fatal("memory allocation failure");
		ISC_LIST_APPEND(server_list, srv, link);
	}
}

static isc_result_t
add_nameserver(lwres_conf_t *confdata, const char *addr, int af) {

	int i = confdata->nsnext;

	if (confdata->nsnext >= LWRES_CONFMAXNAMESERVERS)
		return (ISC_R_FAILURE);

	switch (af) {
	case AF_INET:
		confdata->nameservers[i].family = LWRES_ADDRTYPE_V4;
		confdata->nameservers[i].length = NS_INADDRSZ;
		break;
	case AF_INET6:
		confdata->nameservers[i].family = LWRES_ADDRTYPE_V6;
		confdata->nameservers[i].length = NS_IN6ADDRSZ;
		break;
	default:
		return (ISC_R_FAILURE);
	}

	if (lwres_net_pton(af, addr, &confdata->nameservers[i].address) == 1) {
		confdata->nsnext++;
		return (ISC_R_SUCCESS);
	}
	return (ISC_R_FAILURE);
}

/*%
 * Produce a cloned server list.  The dest list must have already had
 * ISC_LIST_INIT applied.
 */
void
clone_server_list(dig_serverlist_t src, dig_serverlist_t *dest) {
	dig_server_t *srv, *newsrv;

	debug("clone_server_list()");
	srv = ISC_LIST_HEAD(src);
	while (srv != NULL) {
		newsrv = make_server(srv->servername, srv->userarg);
		ISC_LINK_INIT(newsrv, link);
		ISC_LIST_ENQUEUE(*dest, newsrv, link);
		srv = ISC_LIST_NEXT(srv, link);
	}
}

/*%
 * Create an empty lookup structure, which holds all the information needed
 * to get an answer to a user's question.  This structure contains two
 * linked lists: the server list (servers to query) and the query list
 * (outstanding queries which have been made to the listed servers).
 */
dig_lookup_t *
make_empty_lookup(void) {
	dig_lookup_t *looknew;

	debug("make_empty_lookup()");

	INSIST(!free_now);

	looknew = isc_mem_allocate(mctx, sizeof(struct dig_lookup));
	if (looknew == NULL)
		fatal("memory allocation failure in %s:%d",
		       __FILE__, __LINE__);
	looknew->pending = ISC_TRUE;
	looknew->textname[0] = 0;
	looknew->cmdline[0] = 0;
	looknew->rdtype = dns_rdatatype_a;
	looknew->qrdtype = dns_rdatatype_a;
	looknew->rdclass = dns_rdataclass_in;
	looknew->rdtypeset = ISC_FALSE;
	looknew->rdclassset = ISC_FALSE;
	looknew->sendspace = NULL;
	looknew->sendmsg = NULL;
	looknew->name = NULL;
	looknew->oname = NULL;
	looknew->timer = NULL;
	looknew->xfr_q = NULL;
	looknew->current_query = NULL;
	looknew->doing_xfr = ISC_FALSE;
	looknew->ixfr_serial = ISC_FALSE;
	looknew->trace = ISC_FALSE;
	looknew->trace_root = ISC_FALSE;
	looknew->identify = ISC_FALSE;
	looknew->identify_previous_line = ISC_FALSE;
	looknew->ignore = ISC_FALSE;
	looknew->servfail_stops = ISC_TRUE;
	looknew->besteffort = ISC_TRUE;
	looknew->dnssec = ISC_FALSE;
#ifdef DIG_SIGCHASE
	looknew->sigchase = ISC_FALSE;
#if DIG_SIGCHASE_TD
	looknew->do_topdown = ISC_FALSE;
	looknew->trace_root_sigchase = ISC_FALSE;
	looknew->rdtype_sigchaseset = ISC_FALSE;
	looknew->rdtype_sigchase = dns_rdatatype_any;
	looknew->qrdtype_sigchase = dns_rdatatype_any;
	looknew->rdclass_sigchase = dns_rdataclass_in;
	looknew->rdclass_sigchaseset = ISC_FALSE;
#endif
#endif
	looknew->udpsize = 0;
	looknew->edns = -1;
	looknew->recurse = ISC_TRUE;
	looknew->aaonly = ISC_FALSE;
	looknew->adflag = ISC_FALSE;
	looknew->cdflag = ISC_FALSE;
	looknew->ns_search_only = ISC_FALSE;
	looknew->origin = NULL;
	looknew->tsigctx = NULL;
	looknew->querysig = NULL;
	looknew->retries = tries;
	looknew->nsfound = 0;
	looknew->tcp_mode = ISC_FALSE;
	looknew->ip6_int = ISC_FALSE;
	looknew->comments = ISC_TRUE;
	looknew->stats = ISC_TRUE;
	looknew->section_question = ISC_TRUE;
	looknew->section_answer = ISC_TRUE;
	looknew->section_authority = ISC_TRUE;
	looknew->section_additional = ISC_TRUE;
	looknew->new_search = ISC_FALSE;
	looknew->done_as_is = ISC_FALSE;
	looknew->need_search = ISC_FALSE;
	ISC_LINK_INIT(looknew, link);
	ISC_LIST_INIT(looknew->q);
	ISC_LIST_INIT(looknew->my_server_list);
	return (looknew);
}

/*%
 * Clone a lookup, perhaps copying the server list.  This does not clone
 * the query list, since it will be regenerated by the setup_lookup()
 * function, nor does it queue up the new lookup for processing.
 * Caution: If you don't clone the servers, you MUST clone the server
 * list seperately from somewhere else, or construct it by hand.
 */
dig_lookup_t *
clone_lookup(dig_lookup_t *lookold, isc_boolean_t servers) {
	dig_lookup_t *looknew;

	debug("clone_lookup()");

	INSIST(!free_now);

	looknew = make_empty_lookup();
	INSIST(looknew != NULL);
	strncpy(looknew->textname, lookold->textname, MXNAME);
#if DIG_SIGCHASE_TD
	strncpy(looknew->textnamesigchase, lookold->textnamesigchase, MXNAME);
#endif
	strncpy(looknew->cmdline, lookold->cmdline, MXNAME);
	looknew->textname[MXNAME-1] = 0;
	looknew->rdtype = lookold->rdtype;
	looknew->qrdtype = lookold->qrdtype;
	looknew->rdclass = lookold->rdclass;
	looknew->rdtypeset = lookold->rdtypeset;
	looknew->rdclassset = lookold->rdclassset;
	looknew->doing_xfr = lookold->doing_xfr;
	looknew->ixfr_serial = lookold->ixfr_serial;
	looknew->trace = lookold->trace;
	looknew->trace_root = lookold->trace_root;
	looknew->identify = lookold->identify;
	looknew->identify_previous_line = lookold->identify_previous_line;
	looknew->ignore = lookold->ignore;
	looknew->servfail_stops = lookold->servfail_stops;
	looknew->besteffort = lookold->besteffort;
	looknew->dnssec = lookold->dnssec;
#ifdef DIG_SIGCHASE
	looknew->sigchase = lookold->sigchase;
#if DIG_SIGCHASE_TD
	looknew->do_topdown = lookold->do_topdown;
	looknew->trace_root_sigchase = lookold->trace_root_sigchase;
	looknew->rdtype_sigchaseset = lookold->rdtype_sigchaseset;
	looknew->rdtype_sigchase = lookold->rdtype_sigchase;
	looknew->qrdtype_sigchase = lookold->qrdtype_sigchase;
	looknew->rdclass_sigchase = lookold->rdclass_sigchase;
	looknew->rdclass_sigchaseset = lookold->rdclass_sigchaseset;
#endif
#endif
	looknew->udpsize = lookold->udpsize;
	looknew->edns = lookold->edns;
	looknew->recurse = lookold->recurse;
	looknew->aaonly = lookold->aaonly;
	looknew->adflag = lookold->adflag;
	looknew->cdflag = lookold->cdflag;
	looknew->ns_search_only = lookold->ns_search_only;
	looknew->tcp_mode = lookold->tcp_mode;
	looknew->comments = lookold->comments;
	looknew->stats = lookold->stats;
	looknew->section_question = lookold->section_question;
	looknew->section_answer = lookold->section_answer;
	looknew->section_authority = lookold->section_authority;
	looknew->section_additional = lookold->section_additional;
	looknew->retries = lookold->retries;
	looknew->tsigctx = NULL;
	looknew->need_search = lookold->need_search;
	looknew->done_as_is = lookold->done_as_is;

	if (servers)
		clone_server_list(lookold->my_server_list,
				  &looknew->my_server_list);
	return (looknew);
}

/*%
 * Requeue a lookup for further processing, perhaps copying the server
 * list.  The new lookup structure is returned to the caller, and is
 * queued for processing.  If servers are not cloned in the requeue, they
 * must be added before allowing the current event to complete, since the
 * completion of the event may result in the next entry on the lookup
 * queue getting run.
 */
dig_lookup_t *
requeue_lookup(dig_lookup_t *lookold, isc_boolean_t servers) {
	dig_lookup_t *looknew;

	debug("requeue_lookup()");

	lookup_counter++;
	if (lookup_counter > LOOKUP_LIMIT)
		fatal("too many lookups");

	looknew = clone_lookup(lookold, servers);
	INSIST(looknew != NULL);

	debug("before insertion, init@%p -> %p, new@%p -> %p",
	      lookold, lookold->link.next, looknew, looknew->link.next);
	ISC_LIST_PREPEND(lookup_list, looknew, link);
	debug("after insertion, init -> %p, new = %p, new -> %p",
	      lookold, looknew, looknew->link.next);
	return (looknew);
}


static void
setup_text_key(void) {
	isc_result_t result;
	dns_name_t keyname;
	isc_buffer_t secretbuf;
	int secretsize;
	unsigned char *secretstore;

	debug("setup_text_key()");
	result = isc_buffer_allocate(mctx, &namebuf, MXNAME);
	check_result(result, "isc_buffer_allocate");
	dns_name_init(&keyname, NULL);
	check_result(result, "dns_name_init");
	isc_buffer_putstr(namebuf, keynametext);
	secretsize = strlen(keysecret) * 3 / 4;
	secretstore = isc_mem_allocate(mctx, secretsize);
	if (secretstore == NULL)
		fatal("memory allocation failure in %s:%d",
		      __FILE__, __LINE__);
	isc_buffer_init(&secretbuf, secretstore, secretsize);
	result = isc_base64_decodestring(keysecret, &secretbuf);
	if (result != ISC_R_SUCCESS)
		goto failure;
	
	secretsize = isc_buffer_usedlength(&secretbuf);

	result = dns_name_fromtext(&keyname, namebuf,
				   dns_rootname, ISC_FALSE,
				   namebuf);
	if (result != ISC_R_SUCCESS)
		goto failure;

	result = dns_tsigkey_create(&keyname, hmacname, secretstore,
				    secretsize, ISC_FALSE, NULL, 0, 0, mctx,
				    NULL, &key);
 failure:
	if (result != ISC_R_SUCCESS)
		printf(";; Couldn't create key %s: %s\n",
		       keynametext, isc_result_totext(result));
	else
		dst_key_setbits(key->key, digestbits);

	isc_mem_free(mctx, secretstore);
	dns_name_invalidate(&keyname);
	isc_buffer_free(&namebuf);
}

static void
setup_file_key(void) {
	isc_result_t result;
	dst_key_t *dstkey = NULL;

	debug("setup_file_key()");
	result = dst_key_fromnamedfile(keyfile, DST_TYPE_PRIVATE | DST_TYPE_KEY,
				       mctx, &dstkey);
	if (result != ISC_R_SUCCESS) {
		fprintf(stderr, "Couldn't read key from %s: %s\n",
			keyfile, isc_result_totext(result));
		goto failure;
	}

	switch (dst_key_alg(dstkey)) {
	case DST_ALG_HMACMD5:
		hmacname = DNS_TSIG_HMACMD5_NAME;
		break;
	case DST_ALG_HMACSHA1:
		hmacname = DNS_TSIG_HMACSHA1_NAME;
		break;
	case DST_ALG_HMACSHA224:
		hmacname = DNS_TSIG_HMACSHA224_NAME;
		break;
	case DST_ALG_HMACSHA256:
		hmacname = DNS_TSIG_HMACSHA256_NAME;
		break;
	case DST_ALG_HMACSHA384:
		hmacname = DNS_TSIG_HMACSHA384_NAME;
		break;
	case DST_ALG_HMACSHA512:
		hmacname = DNS_TSIG_HMACSHA512_NAME;