1 /** @file
2 Copyright (c) 1999 - 2014, Intel Corporation. All rights reserved.<BR>
3 This program and the accompanying materials are licensed and made available
4 under the terms and conditions of the BSD License which accompanies this
5 distribution. The full text of the license may be found at
6 http://opensource.org/licenses/bsd-license.php.
7
8 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
9 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
10 **/
11 /*
12 * Copyright (c) 1996 by Internet Software Consortium.
13 *
14 * Permission to use, copy, modify, and distribute this software for any
15 * purpose with or without fee is hereby granted, provided that the above
16 * copyright notice and this permission notice appear in all copies.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
19 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
21 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
22 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
23 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
24 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
25 * SOFTWARE.
26 */
27
28 /*
29 * Portions copyright (c) 1999, 2000
30 * Intel Corporation.
31 * All rights reserved.
32 *
33 * Redistribution and use in source and binary forms, with or without
34 * modification, are permitted provided that the following conditions
35 * are met:
36 *
37 * 1. Redistributions of source code must retain the above copyright
38 * notice, this list of conditions and the following disclaimer.
39 *
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 *
44 * 3. All advertising materials mentioning features or use of this software
45 * must display the following acknowledgement:
46 *
47 * This product includes software developed by Intel Corporation and
48 * its contributors.
49 *
50 * 4. Neither the name of Intel Corporation or its contributors may be
51 * used to endorse or promote products derived from this software
52 * without specific prior written permission.
53 *
54 * THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION AND CONTRIBUTORS ``AS IS''
55 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57 * ARE DISCLAIMED. IN NO EVENT SHALL INTEL CORPORATION OR CONTRIBUTORS BE
58 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
59 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
60 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
61 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
62 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
63 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
64 * THE POSSIBILITY OF SUCH DAMAGE.
65 *
66 */
67
68 /*
69 * Based on the Dynamic DNS reference implementation by Viraj Bais
70 * <viraj_bais@ccm.fm.intel.com>
71 */
72
73 #include <sys/types.h>
74 #include <sys/param.h>
75
76 #include <netinet/in.h>
77 #include <arpa/nameser.h>
78 #include <arpa/inet.h>
79
80 #include <errno.h>
81 #include <limits.h>
82 #include <netdb.h>
83 #include <resolv.h>
84 #include <stdio.h>
85 #include <stdlib.h>
86 #include <string.h>
87 #include <unistd.h>
88 #include <ctype.h>
89
90 #include "res_config.h"
91
92 static int getnum_str(u_char **, u_char *);
93 static int getword_str(char *, int, u_char **, u_char *);
94
95 #define ShrinkBuffer(x) if ((buflen -= x) < 0) return (-2);
96
97 /*
98 * Form update packets.
99 * Returns the size of the resulting packet if no error
100 * On error,
101 * returns -1 if error in reading a word/number in rdata
102 * portion for update packets
103 * -2 if length of buffer passed is insufficient
104 * -3 if zone section is not the first section in
105 * the linked list, or section order has a problem
106 * -4 on a number overflow
107 * -5 unknown operation or no records
108 */
109 int
res_mkupdate(ns_updrec * rrecp_in,u_char * buf,int buflen)110 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
111 ns_updrec *rrecp_start = rrecp_in;
112 HEADER *hp;
113 u_char *cp, *sp2, *startp, *endp;
114 int n, i, soanum, multiline;
115 ns_updrec *rrecp;
116 struct in_addr ina;
117 char buf2[MAXDNAME];
118 int section, numrrs = 0, counts[ns_s_max];
119 u_int16_t rtype, rclass;
120 u_int32_t n1, rttl;
121 u_char *dnptrs[20], **dpp, **lastdnptr;
122
123 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
124 h_errno = NETDB_INTERNAL;
125 return (-1);
126 }
127
128 /*
129 * Initialize header fields.
130 */
131 if ((buf == NULL) || (buflen < HFIXEDSZ))
132 return (-1);
133 memset(buf, 0, HFIXEDSZ);
134 hp = (HEADER *) buf;
135 hp->id = htons(++_res.id);
136 hp->opcode = ns_o_update;
137 hp->rcode = NOERROR;
138 cp = buf + HFIXEDSZ;
139 buflen -= HFIXEDSZ;
140 dpp = dnptrs;
141 *dpp++ = buf;
142 *dpp++ = NULL;
143 lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
144
145 if (rrecp_start == NULL)
146 return (-5);
147 else if (rrecp_start->r_section != S_ZONE)
148 return (-3);
149
150 memset(counts, 0, sizeof counts);
151 for (rrecp = rrecp_start; rrecp; rrecp = rrecp->r_grpnext) {
152 numrrs++;
153 section = rrecp->r_section;
154 if (section < 0 || section >= ns_s_max)
155 return (-1);
156 counts[section]++;
157 for (i = section + 1; i < ns_s_max; i++)
158 if (counts[i])
159 return (-3);
160 rtype = rrecp->r_type;
161 rclass = rrecp->r_class;
162 rttl = rrecp->r_ttl;
163 /* overload class and type */
164 if (section == S_PREREQ) {
165 rttl = 0;
166 switch (rrecp->r_opcode) {
167 case YXDOMAIN:
168 rclass = C_ANY;
169 rtype = T_ANY;
170 rrecp->r_size = 0;
171 break;
172 case NXDOMAIN:
173 rclass = C_NONE;
174 rtype = T_ANY;
175 rrecp->r_size = 0;
176 break;
177 case NXRRSET:
178 rclass = C_NONE;
179 rrecp->r_size = 0;
180 break;
181 case YXRRSET:
182 if (rrecp->r_size == 0)
183 rclass = C_ANY;
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 } else if (section == S_UPDATE) {
193 switch (rrecp->r_opcode) {
194 case DELETE:
195 rclass = rrecp->r_size == 0 ? C_ANY : C_NONE;
196 break;
197 case ADD:
198 break;
199 default:
200 fprintf(stderr,
201 "res_mkupdate: incorrect opcode: %d\n",
202 rrecp->r_opcode);
203 fflush(stderr);
204 return (-1);
205 }
206 }
207
208 /*
209 * XXX appending default domain to owner name is omitted,
210 * fqdn must be provided
211 */
212 if ((n = dn_comp(rrecp->r_dname, cp, buflen, dnptrs,
213 lastdnptr)) < 0)
214 return (-1);
215 cp += n;
216 ShrinkBuffer(n + 2*INT16SZ);
217 PUTSHORT(rtype, cp);
218 PUTSHORT(rclass, cp);
219 if (section == S_ZONE) {
220 if (numrrs != 1 || rrecp->r_type != T_SOA)
221 return (-3);
222 continue;
223 }
224 ShrinkBuffer(INT32SZ + INT16SZ);
225 PUTLONG(rttl, cp);
226 sp2 = cp; /* save pointer to length byte */
227 cp += INT16SZ;
228 if (rrecp->r_size == 0) {
229 if (section == S_UPDATE && rclass != C_ANY)
230 return (-1);
231 else {
232 PUTSHORT(0, sp2);
233 continue;
234 }
235 }
236 startp = rrecp->r_data;
237 endp = startp + rrecp->r_size - 1;
238 /* XXX this should be done centrally. */
239 switch (rrecp->r_type) {
240 case T_A:
241 if (!getword_str(buf2, sizeof buf2, &startp, endp))
242 return (-1);
243 if (!inet_aton(buf2, &ina))
244 return (-1);
245 n1 = ntohl(ina.s_addr);
246 ShrinkBuffer(INT32SZ);
247 PUTLONG(n1, cp);
248 break;
249 case T_CNAME:
250 case T_MB:
251 case T_MG:
252 case T_MR:
253 case T_NS:
254 case T_PTR:
255 if (!getword_str(buf2, sizeof buf2, &startp, endp))
256 return (-1);
257 n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
258 if (n < 0)
259 return (-1);
260 cp += n;
261 ShrinkBuffer(n);
262 break;
263 case T_MINFO:
264 case T_SOA:
265 case T_RP:
266 for (i = 0; i < 2; i++) {
267 if (!getword_str(buf2, sizeof buf2, &startp,
268 endp))
269 return (-1);
270 n = dn_comp(buf2, cp, buflen,
271 dnptrs, lastdnptr);
272 if (n < 0)
273 return (-1);
274 cp += n;
275 ShrinkBuffer(n);
276 }
277 if (rrecp->r_type == T_SOA) {
278 ShrinkBuffer(5 * INT32SZ);
279 while (isspace(*startp) || !*startp)
280 startp++;
281 if (*startp == '(') {
282 multiline = 1;
283 startp++;
284 } else
285 multiline = 0;
286 /* serial, refresh, retry, expire, minimum */
287 for (i = 0; i < 5; i++) {
288 soanum = getnum_str(&startp, endp);
289 if (soanum < 0)
290 return (-1);
291 PUTLONG(soanum, cp);
292 }
293 if (multiline) {
294 while (isspace(*startp) || !*startp)
295 startp++;
296 if (*startp != ')')
297 return (-1);
298 }
299 }
300 break;
301 case T_MX:
302 case T_AFSDB:
303 case T_RT:
304 n = getnum_str(&startp, endp);
305 if (n < 0)
306 return (-1);
307 PUTSHORT(n, cp);
308 ShrinkBuffer(INT16SZ);
309 if (!getword_str(buf2, sizeof buf2, &startp, endp))
310 return (-1);
311 n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
312 if (n < 0)
313 return (-1);
314 cp += n;
315 ShrinkBuffer(n);
316 break;
317 case T_PX:
318 n = getnum_str(&startp, endp);
319 if (n < 0)
320 return (-1);
321 PUTSHORT(n, cp);
322 ShrinkBuffer(INT16SZ);
323 for (i = 0; i < 2; i++) {
324 if (!getword_str(buf2, sizeof buf2, &startp,
325 endp))
326 return (-1);
327 n = dn_comp(buf2, cp, buflen, dnptrs,
328 lastdnptr);
329 if (n < 0)
330 return (-1);
331 cp += n;
332 ShrinkBuffer(n);
333 }
334 break;
335 case T_WKS:
336 case T_HINFO:
337 case T_TXT:
338 case T_X25:
339 case T_ISDN:
340 case T_NSAP:
341 case T_LOC:
342 /* XXX - more fine tuning needed here */
343 ShrinkBuffer(rrecp->r_size);
344 memcpy(cp, rrecp->r_data, rrecp->r_size);
345 cp += rrecp->r_size;
346 break;
347 default:
348 return (-1);
349 } /*switch*/
350 n = (u_int16_t)((cp - sp2) - INT16SZ);
351 PUTSHORT(n, sp2);
352 } /*for*/
353
354 hp->qdcount = htons(counts[0]);
355 hp->ancount = htons(counts[1]);
356 hp->nscount = htons(counts[2]);
357 hp->arcount = htons(counts[3]);
358 return ((int)(cp - buf));
359 }
360
361 /*
362 * Get a whitespace delimited word from a string (not file)
363 * into buf. modify the start pointer to point after the
364 * word in the string.
365 */
366 static int
getword_str(char * buf,int size,u_char ** startpp,u_char * endp)367 getword_str(char *buf, int size, u_char **startpp, u_char *endp) {
368 char *cp;
369 int c;
370
371 for (cp = buf; *startpp <= endp; ) {
372 c = **startpp;
373 if (isspace(c) || c == '\0') {
374 if (cp != buf) /* trailing whitespace */
375 break;
376 else { /* leading whitespace */
377 (*startpp)++;
378 continue;
379 }
380 }
381 (*startpp)++;
382 if (cp >= buf+size-1)
383 break;
384 *cp++ = (u_char)c;
385 }
386 *cp = '\0';
387 return (cp != buf);
388 }
389
390 /*
391 * Get a whitespace delimited number from a string (not file) into buf
392 * update the start pointer to point after the number in the string.
393 */
394 static int
getnum_str(u_char ** startpp,u_char * endp)395 getnum_str(u_char **startpp, u_char *endp) {
396 int c;
397 int n;
398 int seendigit = 0;
399 int m = 0;
400
401 for (n = 0; *startpp <= endp; ) {
402 c = **startpp;
403 if (isspace(c) || c == '\0') {
404 if (seendigit) /* trailing whitespace */
405 break;
406 else { /* leading whitespace */
407 (*startpp)++;
408 continue;
409 }
410 }
411 if (c == ';') {
412 while ((*startpp <= endp) &&
413 ((c = **startpp) != '\n'))
414 (*startpp)++;
415 if (seendigit)
416 break;
417 continue;
418 }
419 if (!isdigit(c)) {
420 if (c == ')' && seendigit) {
421 (*startpp)--;
422 break;
423 }
424 return (-1);
425 }
426 (*startpp)++;
427 n = n * 10 + (c - '0');
428 seendigit = 1;
429 }
430 return (n + m);
431 }
432
433 /*
434 * Allocate a resource record buffer & save rr info.
435 */
436 ns_updrec *
res_mkupdrec(int section,const char * dname,u_int class,u_int type,u_long ttl)437 res_mkupdrec(int section, const char *dname,
438 u_int class, u_int type, u_long ttl) {
439 ns_updrec *rrecp = (ns_updrec *)calloc(1, sizeof(ns_updrec));
440
441 if (!rrecp || !(rrecp->r_dname = strdup(dname)))
442 return (NULL);
443 rrecp->r_class = (u_int16_t)class;
444 rrecp->r_type = (u_int16_t)type;
445 rrecp->r_ttl = (u_int32_t)ttl;
446 rrecp->r_section = (u_int8_t)section;
447 return (rrecp);
448 }
449
450 /*
451 * Free a resource record buffer created by res_mkupdrec.
452 */
453 void
res_freeupdrec(ns_updrec * rrecp)454 res_freeupdrec(ns_updrec *rrecp) {
455 /* Note: freeing r_dp is the caller's responsibility. */
456 if (rrecp->r_dname != NULL)
457 free(rrecp->r_dname);
458 free(rrecp);
459 }
460