1/*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1996-1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/*! \file
19 * \brief
20 * Based on the Dynamic DNS reference implementation by Viraj Bais
21 * <viraj_bais@ccm.fm.intel.com>
22 */
23
24#if !defined(lint) && !defined(SABER)
25static const char rcsid[] = "$Id: res_mkupdate.c,v 1.10 2008/12/11 09:59:00 marka Exp $";
26#endif /* not lint */
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include "port_before.h"
31
32#include <sys/param.h>
33
34#include <netinet/in.h>
35#include <arpa/nameser.h>
36#include <arpa/inet.h>
37
38#include <errno.h>
39#include <limits.h>
40#include <netdb.h>
41#include <resolv.h>
42#include <res_update.h>
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <unistd.h>
47#include <ctype.h>
48
49#ifdef _LIBC
50#include <isc/list.h>
51#endif
52
53#include "port_after.h"
54
55/* Options.  Leave them on. */
56#ifndef	DEBUG
57#define	DEBUG
58#endif
59#define MAXPORT 1024
60
61static int getnum_str(u_char **, u_char *);
62static int gethexnum_str(u_char **, u_char *);
63static int getword_str(char *, int, u_char **, u_char *);
64static int getstr_str(char *, int, u_char **, u_char *);
65
66#define ShrinkBuffer(x)  if ((buflen -= x) < 0) return (-2);
67
68/* Forward. */
69
70#ifdef _LIBC
71static
72#endif
73int res_protocolnumber(const char *);
74#ifdef _LIBC
75static
76#endif
77int res_servicenumber(const char *);
78
79/*%
80 * Form update packets.
81 * Returns the size of the resulting packet if no error
82 *
83 * On error,
84 *	returns
85 *\li              -1 if error in reading a word/number in rdata
86 *		   portion for update packets
87 *\li		-2 if length of buffer passed is insufficient
88 *\li		-3 if zone section is not the first section in
89 *		   the linked list, or section order has a problem
90 *\li		-4 on a number overflow
91 *\li		-5 unknown operation or no records
92 */
93int
94res_nmkupdate(res_state statp, ns_updrec *rrecp_in, u_char *buf, int buflen) {
95	ns_updrec *rrecp_start = rrecp_in;
96	HEADER *hp;
97	u_char *cp, *sp2, *startp, *endp;
98	int n, i, soanum, multiline;
99	ns_updrec *rrecp;
100	struct in_addr ina;
101	struct in6_addr in6a;
102        char buf2[MAXDNAME];
103	u_char buf3[MAXDNAME];
104	int section, numrrs = 0, counts[ns_s_max];
105	u_int16_t rtype, rclass;
106	u_int32_t n1, rttl;
107	u_char *dnptrs[20], **dpp, **lastdnptr;
108#ifndef _LIBC
109	int siglen;
110#endif
111	int keylen, certlen;
112
113	/*
114	 * Initialize header fields.
115	 */
116	if ((buf == NULL) || (buflen < HFIXEDSZ))
117		return (-1);
118	memset(buf, 0, HFIXEDSZ);
119	hp = (HEADER *) buf;
120	statp->id = res_nrandomid(statp);
121	hp->id = htons(statp->id);
122	hp->opcode = ns_o_update;
123	hp->rcode = NOERROR;
124	cp = buf + HFIXEDSZ;
125	buflen -= HFIXEDSZ;
126	dpp = dnptrs;
127	*dpp++ = buf;
128	*dpp++ = NULL;
129	lastdnptr = dnptrs + nitems(dnptrs);
130
131	if (rrecp_start == NULL)
132		return (-5);
133	else if (rrecp_start->r_section != S_ZONE)
134		return (-3);
135
136	memset(counts, 0, sizeof counts);
137	for (rrecp = rrecp_start; rrecp; rrecp = NEXT(rrecp, r_glink)) {
138		numrrs++;
139                section = rrecp->r_section;
140		if (section < 0 || section >= ns_s_max)
141			return (-1);
142		counts[section]++;
143		for (i = section + 1; i < ns_s_max; i++)
144			if (counts[i])
145				return (-3);
146		rtype = rrecp->r_type;
147		rclass = rrecp->r_class;
148		rttl = rrecp->r_ttl;
149		/* overload class and type */
150		if (section == S_PREREQ) {
151			rttl = 0;
152			switch (rrecp->r_opcode) {
153			case YXDOMAIN:
154				rclass = C_ANY;
155				rtype = T_ANY;
156				rrecp->r_size = 0;
157				break;
158			case NXDOMAIN:
159				rclass = C_NONE;
160				rtype = T_ANY;
161				rrecp->r_size = 0;
162				break;
163			case NXRRSET:
164				rclass = C_NONE;
165				rrecp->r_size = 0;
166				break;
167			case YXRRSET:
168				if (rrecp->r_size == 0)
169					rclass = C_ANY;
170				break;
171			default:
172				fprintf(stderr,
173					"res_mkupdate: incorrect opcode: %d\n",
174					rrecp->r_opcode);
175				fflush(stderr);
176				return (-1);
177			}
178		} else if (section == S_UPDATE) {
179			switch (rrecp->r_opcode) {
180			case DELETE:
181				rclass = rrecp->r_size == 0 ? C_ANY : C_NONE;
182				break;
183			case ADD:
184				break;
185			default:
186				fprintf(stderr,
187					"res_mkupdate: incorrect opcode: %d\n",
188					rrecp->r_opcode);
189				fflush(stderr);
190				return (-1);
191			}
192		}
193
194		/*
195		 * XXX	appending default domain to owner name is omitted,
196		 *	fqdn must be provided
197		 */
198		if ((n = dn_comp(rrecp->r_dname, cp, buflen, dnptrs,
199				 lastdnptr)) < 0)
200			return (-1);
201		cp += n;
202		ShrinkBuffer(n + 2*INT16SZ);
203		PUTSHORT(rtype, cp);
204		PUTSHORT(rclass, cp);
205		if (section == S_ZONE) {
206			if (numrrs != 1 || rrecp->r_type != T_SOA)
207				return (-3);
208			continue;
209		}
210		ShrinkBuffer(INT32SZ + INT16SZ);
211		PUTLONG(rttl, cp);
212		sp2 = cp;  /*%< save pointer to length byte */
213		cp += INT16SZ;
214		if (rrecp->r_size == 0) {
215			if (section == S_UPDATE && rclass != C_ANY)
216				return (-1);
217			else {
218				PUTSHORT(0, sp2);
219				continue;
220			}
221		}
222		startp = rrecp->r_data;
223		endp = startp + rrecp->r_size - 1;
224		/* XXX this should be done centrally. */
225		switch (rrecp->r_type) {
226		case T_A:
227			if (!getword_str(buf2, sizeof buf2, &startp, endp))
228				return (-1);
229			if (!inet_aton(buf2, &ina))
230				return (-1);
231			n1 = ntohl(ina.s_addr);
232			ShrinkBuffer(INT32SZ);
233			PUTLONG(n1, cp);
234			break;
235		case T_CNAME:
236		case T_MB:
237		case T_MG:
238		case T_MR:
239		case T_NS:
240		case T_PTR:
241		case ns_t_dname:
242			if (!getword_str(buf2, sizeof buf2, &startp, endp))
243				return (-1);
244			n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
245			if (n < 0)
246				return (-1);
247			cp += n;
248			ShrinkBuffer(n);
249			break;
250		case T_MINFO:
251		case T_SOA:
252		case T_RP:
253			for (i = 0; i < 2; i++) {
254				if (!getword_str(buf2, sizeof buf2, &startp,
255						 endp))
256				return (-1);
257				n = dn_comp(buf2, cp, buflen,
258					    dnptrs, lastdnptr);
259				if (n < 0)
260					return (-1);
261				cp += n;
262				ShrinkBuffer(n);
263			}
264			if (rrecp->r_type == T_SOA) {
265				ShrinkBuffer(5 * INT32SZ);
266				while (isspace(*startp) || !*startp)
267					startp++;
268				if (*startp == '(') {
269					multiline = 1;
270					startp++;
271				} else
272					multiline = 0;
273				/* serial, refresh, retry, expire, minimum */
274				for (i = 0; i < 5; i++) {
275					soanum = getnum_str(&startp, endp);
276					if (soanum < 0)
277						return (-1);
278					PUTLONG(soanum, cp);
279				}
280				if (multiline) {
281					while (isspace(*startp) || !*startp)
282						startp++;
283					if (*startp != ')')
284						return (-1);
285				}
286			}
287			break;
288		case T_MX:
289		case T_AFSDB:
290		case T_RT:
291			n = getnum_str(&startp, endp);
292			if (n < 0)
293				return (-1);
294			ShrinkBuffer(INT16SZ);
295			PUTSHORT(n, cp);
296			if (!getword_str(buf2, sizeof buf2, &startp, endp))
297				return (-1);
298			n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
299			if (n < 0)
300				return (-1);
301			cp += n;
302			ShrinkBuffer(n);
303			break;
304		case T_SRV:
305			n = getnum_str(&startp, endp);
306			if (n < 0)
307				return (-1);
308			ShrinkBuffer(INT16SZ);
309			PUTSHORT(n, cp);
310
311			n = getnum_str(&startp, endp);
312			if (n < 0)
313				return (-1);
314			ShrinkBuffer(INT16SZ);
315			PUTSHORT(n, cp);
316
317			n = getnum_str(&startp, endp);
318			if (n < 0)
319				return (-1);
320			ShrinkBuffer(INT16SZ);
321			PUTSHORT(n, cp);
322
323			if (!getword_str(buf2, sizeof buf2, &startp, endp))
324				return (-1);
325			n = dn_comp(buf2, cp, buflen, NULL, NULL);
326			if (n < 0)
327				return (-1);
328			cp += n;
329			ShrinkBuffer(n);
330			break;
331		case T_PX:
332			n = getnum_str(&startp, endp);
333			if (n < 0)
334				return (-1);
335			PUTSHORT(n, cp);
336			ShrinkBuffer(INT16SZ);
337			for (i = 0; i < 2; i++) {
338				if (!getword_str(buf2, sizeof buf2, &startp,
339						 endp))
340					return (-1);
341				n = dn_comp(buf2, cp, buflen, dnptrs,
342					    lastdnptr);
343				if (n < 0)
344					return (-1);
345				cp += n;
346				ShrinkBuffer(n);
347			}
348			break;
349		case T_WKS: {
350			char bm[MAXPORT/8];
351			unsigned int maxbm = 0;
352
353			if (!getword_str(buf2, sizeof buf2, &startp, endp))
354				return (-1);
355			if (!inet_aton(buf2, &ina))
356				return (-1);
357			n1 = ntohl(ina.s_addr);
358			ShrinkBuffer(INT32SZ);
359			PUTLONG(n1, cp);
360
361			if (!getword_str(buf2, sizeof buf2, &startp, endp))
362				return (-1);
363			if ((i = res_protocolnumber(buf2)) < 0)
364				return (-1);
365			ShrinkBuffer(1);
366			*cp++ = i & 0xff;
367
368			for (i = 0; i < MAXPORT/8 ; i++)
369				bm[i] = 0;
370
371			while (getword_str(buf2, sizeof buf2, &startp, endp)) {
372				if ((n = res_servicenumber(buf2)) <= 0)
373					return (-1);
374
375				if (n < MAXPORT) {
376					bm[n/8] |= (0x80>>(n%8));
377					if ((unsigned)n > maxbm)
378						maxbm = n;
379				} else
380					return (-1);
381			}
382			maxbm = maxbm/8 + 1;
383			ShrinkBuffer(maxbm);
384			memcpy(cp, bm, maxbm);
385			cp += maxbm;
386			break;
387		}
388		case T_HINFO:
389			for (i = 0; i < 2; i++) {
390				if ((n = getstr_str(buf2, sizeof buf2,
391						&startp, endp)) < 0)
392					return (-1);
393				if (n > 255)
394					return (-1);
395				ShrinkBuffer(n+1);
396				*cp++ = n;
397				memcpy(cp, buf2, n);
398				cp += n;
399			}
400			break;
401		case T_TXT:
402			for (;;) {
403				if ((n = getstr_str(buf2, sizeof buf2,
404						&startp, endp)) < 0) {
405					if (cp != (sp2 + INT16SZ))
406						break;
407					return (-1);
408				}
409				if (n > 255)
410					return (-1);
411				ShrinkBuffer(n+1);
412				*cp++ = n;
413				memcpy(cp, buf2, n);
414				cp += n;
415			}
416			break;
417		case T_X25:
418			/* RFC1183 */
419			if ((n = getstr_str(buf2, sizeof buf2, &startp,
420					 endp)) < 0)
421				return (-1);
422			if (n > 255)
423				return (-1);
424			ShrinkBuffer(n+1);
425			*cp++ = n;
426			memcpy(cp, buf2, n);
427			cp += n;
428			break;
429		case T_ISDN:
430			/* RFC1183 */
431			if ((n = getstr_str(buf2, sizeof buf2, &startp,
432					 endp)) < 0)
433				return (-1);
434			if ((n > 255) || (n == 0))
435				return (-1);
436			ShrinkBuffer(n+1);
437			*cp++ = n;
438			memcpy(cp, buf2, n);
439			cp += n;
440			if ((n = getstr_str(buf2, sizeof buf2, &startp,
441					 endp)) < 0)
442				n = 0;
443			if (n > 255)
444				return (-1);
445			ShrinkBuffer(n+1);
446			*cp++ = n;
447			memcpy(cp, buf2, n);
448			cp += n;
449			break;
450		case T_NSAP:
451			if ((n = inet_nsap_addr((char *)startp, (u_char *)buf2, sizeof(buf2))) != 0) {
452				ShrinkBuffer(n);
453				memcpy(cp, buf2, n);
454				cp += n;
455			} else {
456				return (-1);
457			}
458			break;
459		case T_LOC:
460			if ((n = loc_aton((char *)startp, (u_char *)buf2)) != 0) {
461				ShrinkBuffer(n);
462				memcpy(cp, buf2, n);
463				cp += n;
464			} else
465				return (-1);
466			break;
467		case ns_t_sig:
468#ifdef _LIBC
469			return (-1);
470#else
471		    {
472			int sig_type, success, dateerror;
473			u_int32_t exptime, timesigned;
474
475			/* type */
476			if ((n = getword_str(buf2, sizeof buf2,
477					     &startp, endp)) < 0)
478				return (-1);
479			sig_type = sym_ston(__p_type_syms, buf2, &success);
480			if (!success || sig_type == ns_t_any)
481				return (-1);
482			ShrinkBuffer(INT16SZ);
483			PUTSHORT(sig_type, cp);
484			/* alg */
485			n = getnum_str(&startp, endp);
486			if (n < 0)
487				return (-1);
488			ShrinkBuffer(1);
489			*cp++ = n;
490			/* labels */
491			n = getnum_str(&startp, endp);
492			if (n <= 0 || n > 255)
493				return (-1);
494			ShrinkBuffer(1);
495			*cp++ = n;
496			/* ottl  & expire */
497			if (!getword_str(buf2, sizeof buf2, &startp, endp))
498				return (-1);
499			exptime = ns_datetosecs(buf2, &dateerror);
500			if (!dateerror) {
501				ShrinkBuffer(INT32SZ);
502				PUTLONG(rttl, cp);
503			}
504			else {
505				char *ulendp;
506				u_int32_t ottl;
507
508				errno = 0;
509				ottl = strtoul(buf2, &ulendp, 10);
510				if (errno != 0 ||
511				    (ulendp != NULL && *ulendp != '\0'))
512					return (-1);
513				ShrinkBuffer(INT32SZ);
514				PUTLONG(ottl, cp);
515				if (!getword_str(buf2, sizeof buf2, &startp,
516						 endp))
517					return (-1);
518				exptime = ns_datetosecs(buf2, &dateerror);
519				if (dateerror)
520					return (-1);
521			}
522			/* expire */
523			ShrinkBuffer(INT32SZ);
524			PUTLONG(exptime, cp);
525			/* timesigned */
526			if (!getword_str(buf2, sizeof buf2, &startp, endp))
527				return (-1);
528			timesigned = ns_datetosecs(buf2, &dateerror);
529			if (!dateerror) {
530				ShrinkBuffer(INT32SZ);
531				PUTLONG(timesigned, cp);
532			}
533			else
534				return (-1);
535			/* footprint */
536			n = getnum_str(&startp, endp);
537			if (n < 0)
538				return (-1);
539			ShrinkBuffer(INT16SZ);
540			PUTSHORT(n, cp);
541			/* signer name */
542			if (!getword_str(buf2, sizeof buf2, &startp, endp))
543				return (-1);
544			n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
545			if (n < 0)
546				return (-1);
547			cp += n;
548			ShrinkBuffer(n);
549			/* sig */
550			if ((n = getword_str(buf2, sizeof buf2,
551					     &startp, endp)) < 0)
552				return (-1);
553			siglen = b64_pton(buf2, buf3, sizeof(buf3));
554			if (siglen < 0)
555				return (-1);
556			ShrinkBuffer(siglen);
557			memcpy(cp, buf3, siglen);
558			cp += siglen;
559			break;
560		    }
561#endif
562		case ns_t_key:
563			/* flags */
564			n = gethexnum_str(&startp, endp);
565			if (n < 0)
566				return (-1);
567			ShrinkBuffer(INT16SZ);
568			PUTSHORT(n, cp);
569			/* proto */
570			n = getnum_str(&startp, endp);
571			if (n < 0)
572				return (-1);
573			ShrinkBuffer(1);
574			*cp++ = n;
575			/* alg */
576			n = getnum_str(&startp, endp);
577			if (n < 0)
578				return (-1);
579			ShrinkBuffer(1);
580			*cp++ = n;
581			/* key */
582			if ((n = getword_str(buf2, sizeof buf2,
583					     &startp, endp)) < 0)
584				return (-1);
585			keylen = b64_pton(buf2, buf3, sizeof(buf3));
586			if (keylen < 0)
587				return (-1);
588			ShrinkBuffer(keylen);
589			memcpy(cp, buf3, keylen);
590			cp += keylen;
591			break;
592		case ns_t_nxt:
593		    {
594			int success, nxt_type;
595			u_char data[32];
596			int maxtype;
597
598			/* next name */
599			if (!getword_str(buf2, sizeof buf2, &startp, endp))
600				return (-1);
601			n = dn_comp(buf2, cp, buflen, NULL, NULL);
602			if (n < 0)
603				return (-1);
604			cp += n;
605			ShrinkBuffer(n);
606			maxtype = 0;
607			memset(data, 0, sizeof data);
608			for (;;) {
609				if (!getword_str(buf2, sizeof buf2, &startp,
610						 endp))
611					break;
612				nxt_type = sym_ston(__p_type_syms, buf2,
613						    &success);
614				if (!success || !ns_t_rr_p(nxt_type))
615					return (-1);
616				NS_NXT_BIT_SET(nxt_type, data);
617				if (nxt_type > maxtype)
618					maxtype = nxt_type;
619			}
620			n = maxtype/NS_NXT_BITS+1;
621			ShrinkBuffer(n);
622			memcpy(cp, data, n);
623			cp += n;
624			break;
625		    }
626		case ns_t_cert:
627			/* type */
628			n = getnum_str(&startp, endp);
629			if (n < 0)
630				return (-1);
631			ShrinkBuffer(INT16SZ);
632			PUTSHORT(n, cp);
633			/* key tag */
634			n = getnum_str(&startp, endp);
635			if (n < 0)
636				return (-1);
637			ShrinkBuffer(INT16SZ);
638			PUTSHORT(n, cp);
639			/* alg */
640			n = getnum_str(&startp, endp);
641			if (n < 0)
642				return (-1);
643			ShrinkBuffer(1);
644			*cp++ = n;
645			/* cert */
646			if ((n = getword_str(buf2, sizeof buf2,
647					     &startp, endp)) < 0)
648				return (-1);
649			certlen = b64_pton(buf2, buf3, sizeof(buf3));
650			if (certlen < 0)
651				return (-1);
652			ShrinkBuffer(certlen);
653			memcpy(cp, buf3, certlen);
654			cp += certlen;
655			break;
656		case ns_t_aaaa:
657			if (!getword_str(buf2, sizeof buf2, &startp, endp))
658				return (-1);
659			if (inet_pton(AF_INET6, buf2, &in6a) <= 0)
660				return (-1);
661			ShrinkBuffer(NS_IN6ADDRSZ);
662			memcpy(cp, &in6a, NS_IN6ADDRSZ);
663			cp += NS_IN6ADDRSZ;
664			break;
665		case ns_t_naptr:
666			/* Order Preference Flags Service Replacement Regexp */
667			/* Order */
668			n = getnum_str(&startp, endp);
669			if (n < 0 || n > 65535)
670				return (-1);
671			ShrinkBuffer(INT16SZ);
672			PUTSHORT(n, cp);
673			/* Preference */
674			n = getnum_str(&startp, endp);
675			if (n < 0 || n > 65535)
676				return (-1);
677			ShrinkBuffer(INT16SZ);
678			PUTSHORT(n, cp);
679			/* Flags */
680			if ((n = getstr_str(buf2, sizeof buf2,
681					&startp, endp)) < 0) {
682				return (-1);
683			}
684			if (n > 255)
685				return (-1);
686			ShrinkBuffer(n+1);
687			*cp++ = n;
688			memcpy(cp, buf2, n);
689			cp += n;
690			/* Service Classes */
691			if ((n = getstr_str(buf2, sizeof buf2,
692					&startp, endp)) < 0) {
693				return (-1);
694			}
695			if (n > 255)
696				return (-1);
697			ShrinkBuffer(n+1);
698			*cp++ = n;
699			memcpy(cp, buf2, n);
700			cp += n;
701			/* Pattern */
702			if ((n = getstr_str(buf2, sizeof buf2,
703					&startp, endp)) < 0) {
704				return (-1);
705			}
706			if (n > 255)
707				return (-1);
708			ShrinkBuffer(n+1);
709			*cp++ = n;
710			memcpy(cp, buf2, n);
711			cp += n;
712			/* Replacement */
713			if (!getword_str(buf2, sizeof buf2, &startp, endp))
714				return (-1);
715			n = dn_comp(buf2, cp, buflen, NULL, NULL);
716			if (n < 0)
717				return (-1);
718			cp += n;
719			ShrinkBuffer(n);
720			break;
721		default:
722			return (-1);
723		} /*switch*/
724		n = (u_int16_t)((cp - sp2) - INT16SZ);
725		PUTSHORT(n, sp2);
726	} /*for*/
727
728	hp->qdcount = htons(counts[0]);
729	hp->ancount = htons(counts[1]);
730	hp->nscount = htons(counts[2]);
731	hp->arcount = htons(counts[3]);
732	return (cp - buf);
733}
734
735/*%
736 * Get a whitespace delimited word from a string (not file)
737 * into buf. modify the start pointer to point after the
738 * word in the string.
739 */
740static int
741getword_str(char *buf, int size, u_char **startpp, u_char *endp) {
742        char *cp;
743        int c;
744
745        for (cp = buf; *startpp <= endp; ) {
746                c = **startpp;
747                if (isspace(c) || c == '\0') {
748                        if (cp != buf) /*%< trailing whitespace */
749                                break;
750                        else { /*%< leading whitespace */
751                                (*startpp)++;
752                                continue;
753                        }
754                }
755                (*startpp)++;
756                if (cp >= buf+size-1)
757                        break;
758                *cp++ = (u_char)c;
759        }
760        *cp = '\0';
761        return (cp != buf);
762}
763
764/*%
765 * get a white spae delimited string from memory.  Process quoted strings
766 * and \\DDD escapes.  Return length or -1 on error.  Returned string may
767 * contain nulls.
768 */
769static char digits[] = "0123456789";
770static int
771getstr_str(char *buf, int size, u_char **startpp, u_char *endp) {
772        char *cp;
773        int c, c1 = 0;
774	int inquote = 0;
775	int seen_quote = 0;
776	int escape = 0;
777	int dig = 0;
778
779	for (cp = buf; *startpp <= endp; ) {
780                if ((c = **startpp) == '\0')
781			break;
782		/* leading white space */
783		if ((cp == buf) && !seen_quote && isspace(c)) {
784			(*startpp)++;
785			continue;
786		}
787
788		switch (c) {
789		case '\\':
790			if (!escape)  {
791				escape = 1;
792				dig = 0;
793				c1 = 0;
794				(*startpp)++;
795				continue;
796			}
797			goto do_escape;
798		case '"':
799			if (!escape) {
800				inquote = !inquote;
801				seen_quote = 1;
802				(*startpp)++;
803				continue;
804			}
805			/* fall through */
806		default:
807		do_escape:
808			if (escape) {
809				switch (c) {
810				case '0':
811				case '1':
812				case '2':
813				case '3':
814				case '4':
815				case '5':
816				case '6':
817				case '7':
818				case '8':
819				case '9':
820					c1 = c1 * 10 +
821						(strchr(digits, c) - digits);
822
823					if (++dig == 3) {
824						c = c1 &0xff;
825						break;
826					}
827					(*startpp)++;
828					continue;
829				}
830				escape = 0;
831			} else if (!inquote && isspace(c))
832				goto done;
833			if (cp >= buf+size-1)
834				goto done;
835			*cp++ = (u_char)c;
836			(*startpp)++;
837		}
838	}
839 done:
840	*cp = '\0';
841	return ((cp == buf)?  (seen_quote? 0: -1): (cp - buf));
842}
843
844/*%
845 * Get a whitespace delimited base 16 number from a string (not file) into buf
846 * update the start pointer to point after the number in the string.
847 */
848static int
849gethexnum_str(u_char **startpp, u_char *endp) {
850        int c, n;
851        int seendigit = 0;
852        int m = 0;
853
854	if (*startpp + 2 >= endp || strncasecmp((char *)*startpp, "0x", 2) != 0)
855		return getnum_str(startpp, endp);
856	(*startpp)+=2;
857        for (n = 0; *startpp <= endp; ) {
858                c = **startpp;
859                if (isspace(c) || c == '\0') {
860                        if (seendigit) /*%< trailing whitespace */
861                                break;
862                        else { /*%< leading whitespace */
863                                (*startpp)++;
864                                continue;
865                        }
866                }
867                if (c == ';') {
868                        while ((*startpp <= endp) &&
869			       ((c = **startpp) != '\n'))
870					(*startpp)++;
871                        if (seendigit)
872                                break;
873                        continue;
874                }
875                if (!isxdigit(c)) {
876                        if (c == ')' && seendigit) {
877                                (*startpp)--;
878                                break;
879                        }
880			return (-1);
881                }
882                (*startpp)++;
883		if (isdigit(c))
884	                n = n * 16 + (c - '0');
885		else
886			n = n * 16 + (tolower(c) - 'a' + 10);
887                seendigit = 1;
888        }
889        return (n + m);
890}
891
892/*%
893 * Get a whitespace delimited base 10 number from a string (not file) into buf
894 * update the start pointer to point after the number in the string.
895 */
896static int
897getnum_str(u_char **startpp, u_char *endp) {
898        int c, n;
899        int seendigit = 0;
900        int m = 0;
901
902        for (n = 0; *startpp <= endp; ) {
903                c = **startpp;
904                if (isspace(c) || c == '\0') {
905                        if (seendigit) /*%< trailing whitespace */
906                                break;
907                        else { /*%< leading whitespace */
908                                (*startpp)++;
909                                continue;
910                        }
911                }
912                if (c == ';') {
913                        while ((*startpp <= endp) &&
914			       ((c = **startpp) != '\n'))
915					(*startpp)++;
916                        if (seendigit)
917                                break;
918                        continue;
919                }
920                if (!isdigit(c)) {
921                        if (c == ')' && seendigit) {
922                                (*startpp)--;
923                                break;
924                        }
925			return (-1);
926                }
927                (*startpp)++;
928                n = n * 10 + (c - '0');
929                seendigit = 1;
930        }
931        return (n + m);
932}
933
934/*%
935 * Allocate a resource record buffer & save rr info.
936 */
937ns_updrec *
938res_mkupdrec(int section, const char *dname,
939	     u_int class, u_int type, u_long ttl) {
940	ns_updrec *rrecp = (ns_updrec *)calloc(1, sizeof(ns_updrec));
941
942	if (!rrecp || !(rrecp->r_dname = strdup(dname))) {
943		if (rrecp)
944			free((char *)rrecp);
945		return (NULL);
946	}
947	INIT_LINK(rrecp, r_link);
948	INIT_LINK(rrecp, r_glink);
949 	rrecp->r_class = (ns_class)class;
950	rrecp->r_type = (ns_type)type;
951	rrecp->r_ttl = ttl;
952	rrecp->r_section = (ns_sect)section;
953	return (rrecp);
954}
955
956/*%
957 * Free a resource record buffer created by res_mkupdrec.
958 */
959void
960res_freeupdrec(ns_updrec *rrecp) {
961	/* Note: freeing r_dp is the caller's responsibility. */
962	if (rrecp->r_dname != NULL)
963		free(rrecp->r_dname);
964	free(rrecp);
965}
966
967struct valuelist {
968	struct valuelist *	next;
969	struct valuelist *	prev;
970	char *			name;
971	char *			proto;
972	int			port;
973};
974static struct valuelist *servicelist, *protolist;
975
976static void
977res_buildservicelist(void) {
978	struct servent *sp;
979	struct valuelist *slp;
980
981#ifdef MAYBE_HESIOD
982	setservent(0);
983#else
984	setservent(1);
985#endif
986	while ((sp = getservent()) != NULL) {
987		slp = (struct valuelist *)malloc(sizeof(struct valuelist));
988		if (!slp)
989			break;
990		slp->name = strdup(sp->s_name);
991		slp->proto = strdup(sp->s_proto);
992		if ((slp->name == NULL) || (slp->proto == NULL)) {
993			if (slp->name) free(slp->name);
994			if (slp->proto) free(slp->proto);
995			free(slp);
996			break;
997		}
998		slp->port = ntohs((u_int16_t)sp->s_port);  /*%< host byt order */
999		slp->next = servicelist;
1000		slp->prev = NULL;
1001		if (servicelist)
1002			servicelist->prev = slp;
1003		servicelist = slp;
1004	}
1005	endservent();
1006}
1007
1008#ifndef _LIBC
1009void
1010res_destroyservicelist() {
1011	struct valuelist *slp, *slp_next;
1012
1013	for (slp = servicelist; slp != NULL; slp = slp_next) {
1014		slp_next = slp->next;
1015		free(slp->name);
1016		free(slp->proto);
1017		free(slp);
1018	}
1019	servicelist = (struct valuelist *)0;
1020}
1021#endif
1022
1023#ifdef _LIBC
1024static
1025#endif
1026void
1027res_buildprotolist(void) {
1028	struct protoent *pp;
1029	struct valuelist *slp;
1030
1031#ifdef MAYBE_HESIOD
1032	setprotoent(0);
1033#else
1034	setprotoent(1);
1035#endif
1036	while ((pp = getprotoent()) != NULL) {
1037		slp = (struct valuelist *)malloc(sizeof(struct valuelist));
1038		if (!slp)
1039			break;
1040		slp->name = strdup(pp->p_name);
1041		if (slp->name == NULL) {
1042			free(slp);
1043			break;
1044		}
1045		slp->port = pp->p_proto;	/*%< host byte order */
1046		slp->next = protolist;
1047		slp->prev = NULL;
1048		if (protolist)
1049			protolist->prev = slp;
1050		protolist = slp;
1051	}
1052	endprotoent();
1053}
1054
1055#ifndef _LIBC
1056void
1057res_destroyprotolist(void) {
1058	struct valuelist *plp, *plp_next;
1059
1060	for (plp = protolist; plp != NULL; plp = plp_next) {
1061		plp_next = plp->next;
1062		free(plp->name);
1063		free(plp);
1064	}
1065	protolist = (struct valuelist *)0;
1066}
1067#endif
1068
1069static int
1070findservice(const char *s, struct valuelist **list) {
1071	struct valuelist *lp = *list;
1072	int n;
1073
1074	for (; lp != NULL; lp = lp->next)
1075		if (strcasecmp(lp->name, s) == 0) {
1076			if (lp != *list) {
1077				lp->prev->next = lp->next;
1078				if (lp->next)
1079					lp->next->prev = lp->prev;
1080				(*list)->prev = lp;
1081				lp->next = *list;
1082				*list = lp;
1083			}
1084			return (lp->port);	/*%< host byte order */
1085		}
1086	if (sscanf(s, "%d", &n) != 1 || n <= 0)
1087		n = -1;
1088	return (n);
1089}
1090
1091/*%
1092 * Convert service name or (ascii) number to int.
1093 */
1094#ifdef _LIBC
1095static
1096#endif
1097int
1098res_servicenumber(const char *p) {
1099	if (servicelist == (struct valuelist *)0)
1100		res_buildservicelist();
1101	return (findservice(p, &servicelist));
1102}
1103
1104/*%
1105 * Convert protocol name or (ascii) number to int.
1106 */
1107#ifdef _LIBC
1108static
1109#endif
1110int
1111res_protocolnumber(const char *p) {
1112	if (protolist == (struct valuelist *)0)
1113		res_buildprotolist();
1114	return (findservice(p, &protolist));
1115}
1116
1117#ifndef _LIBC
1118static struct servent *
1119cgetservbyport(u_int16_t port, const char *proto) {	/*%< Host byte order. */
1120	struct valuelist **list = &servicelist;
1121	struct valuelist *lp = *list;
1122	static struct servent serv;
1123
1124	port = ntohs(port);
1125	for (; lp != NULL; lp = lp->next) {
1126		if (port != (u_int16_t)lp->port)	/*%< Host byte order. */
1127			continue;
1128		if (strcasecmp(lp->proto, proto) == 0) {
1129			if (lp != *list) {
1130				lp->prev->next = lp->next;
1131				if (lp->next)
1132					lp->next->prev = lp->prev;
1133				(*list)->prev = lp;
1134				lp->next = *list;
1135				*list = lp;
1136			}
1137			serv.s_name = lp->name;
1138			serv.s_port = htons((u_int16_t)lp->port);
1139			serv.s_proto = lp->proto;
1140			return (&serv);
1141		}
1142	}
1143	return (0);
1144}
1145
1146static struct protoent *
1147cgetprotobynumber(int proto) {				/*%< Host byte order. */
1148	struct valuelist **list = &protolist;
1149	struct valuelist *lp = *list;
1150	static struct protoent prot;
1151
1152	for (; lp != NULL; lp = lp->next)
1153		if (lp->port == proto) {		/*%< Host byte order. */
1154			if (lp != *list) {
1155				lp->prev->next = lp->next;
1156				if (lp->next)
1157					lp->next->prev = lp->prev;
1158				(*list)->prev = lp;
1159				lp->next = *list;
1160				*list = lp;
1161			}
1162			prot.p_name = lp->name;
1163			prot.p_proto = lp->port;	/*%< Host byte order. */
1164			return (&prot);
1165		}
1166	return (0);
1167}
1168
1169const char *
1170res_protocolname(int num) {
1171	static char number[8];
1172	struct protoent *pp;
1173
1174	if (protolist == (struct valuelist *)0)
1175		res_buildprotolist();
1176	pp = cgetprotobynumber(num);
1177	if (pp == NULL)  {
1178		(void) sprintf(number, "%d", num);
1179		return (number);
1180	}
1181	return (pp->p_name);
1182}
1183
1184const char *
1185res_servicename(u_int16_t port, const char *proto) {	/*%< Host byte order. */
1186	static char number[8];
1187	struct servent *ss;
1188
1189	if (servicelist == (struct valuelist *)0)
1190		res_buildservicelist();
1191	ss = cgetservbyport(htons(port), proto);
1192	if (ss == NULL)  {
1193		(void) sprintf(number, "%d", port);
1194		return (number);
1195	}
1196	return (ss->s_name);
1197}
1198#endif
1199