resolv.c 43 KB

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  1. /* resolv.c: DNS Resolver
  2. *
  3. * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>,
  4. * The Silver Hammer Group, Ltd.
  5. *
  6. * This library is free software; you can redistribute it and/or
  7. * modify it under the terms of the GNU Library General Public
  8. * License as published by the Free Software Foundation; either
  9. * version 2 of the License, or (at your option) any later version.
  10. *
  11. * 5-Oct-2000 W. Greathouse wgreathouse@smva.com
  12. * Fix memory leak and memory corruption.
  13. * -- Every name resolution resulted in
  14. * a new parse of resolv.conf and new
  15. * copy of nameservers allocated by
  16. * strdup.
  17. * -- Every name resolution resulted in
  18. * a new read of resolv.conf without
  19. * resetting index from prior read...
  20. * resulting in exceeding array bounds.
  21. *
  22. * Limit nameservers read from resolv.conf
  23. *
  24. * Add "search" domains from resolv.conf
  25. *
  26. * Some systems will return a security
  27. * signature along with query answer for
  28. * dynamic DNS entries.
  29. * -- skip/ignore this answer
  30. *
  31. * Include arpa/nameser.h for defines.
  32. *
  33. * General cleanup
  34. *
  35. * 20-Jun-2001 Michal Moskal <malekith@pld.org.pl>
  36. * partial IPv6 support (i.e. gethostbyname2() and resolve_address2()
  37. * functions added), IPv6 nameservers are also supported.
  38. *
  39. * 6-Oct-2001 Jari Korva <jari.korva@iki.fi>
  40. * more IPv6 support (IPv6 support for gethostbyaddr();
  41. * address family parameter and improved IPv6 support for get_hosts_byname
  42. * and read_etc_hosts; getnameinfo() port from glibc; defined
  43. * defined ip6addr_any and in6addr_loopback)
  44. *
  45. * 2-Feb-2002 Erik Andersen <andersee@debian.org>
  46. * Added gethostent(), sethostent(), and endhostent()
  47. *
  48. */
  49. #define __FORCE_GLIBC
  50. #include <features.h>
  51. #include <string.h>
  52. #include <stdio.h>
  53. #include <signal.h>
  54. #include <errno.h>
  55. #include <sys/socket.h>
  56. #include <sys/types.h>
  57. #include <netinet/in.h>
  58. #include <arpa/inet.h>
  59. #include <stdlib.h>
  60. #include <unistd.h>
  61. #include <resolv.h>
  62. #include <netdb.h>
  63. #include <ctype.h>
  64. #include <arpa/nameser.h>
  65. #include <sys/utsname.h>
  66. #include <sys/un.h>
  67. #define MAX_RECURSE 5
  68. #define REPLY_TIMEOUT 10
  69. #define MAX_RETRIES 15
  70. #define MAX_SERVERS 3
  71. #define MAX_SEARCH 4
  72. #undef DEBUG
  73. /*#define DEBUG*/
  74. #ifdef DEBUG
  75. #define DPRINTF(X,args...) fprintf(stderr, X, ##args)
  76. #else
  77. #define DPRINTF(X,args...)
  78. #endif /* DEBUG */
  79. struct resolv_header {
  80. int id;
  81. int qr,opcode,aa,tc,rd,ra,rcode;
  82. int qdcount;
  83. int ancount;
  84. int nscount;
  85. int arcount;
  86. };
  87. struct resolv_question {
  88. char * dotted;
  89. int qtype;
  90. int qclass;
  91. };
  92. struct resolv_answer {
  93. char * dotted;
  94. int atype;
  95. int aclass;
  96. int ttl;
  97. int rdlength;
  98. unsigned char * rdata;
  99. int rdoffset;
  100. };
  101. enum etc_hosts_action {
  102. GET_HOSTS_BYNAME = 0,
  103. GETHOSTENT,
  104. GET_HOSTS_BYADDR,
  105. };
  106. extern int nameservers;
  107. extern char * nameserver[MAX_SERVERS];
  108. extern int searchdomains;
  109. extern char * searchdomain[MAX_SEARCH];
  110. extern int get_hosts_byname_r(const char * name, int type,
  111. struct hostent * result_buf,
  112. char * buf, size_t buflen,
  113. struct hostent ** result,
  114. int * h_errnop);
  115. extern int get_hosts_byaddr_r(const char * addr, int len, int type,
  116. struct hostent * result_buf,
  117. char * buf, size_t buflen,
  118. struct hostent ** result,
  119. int * h_errnop);
  120. extern void __open_etc_hosts(FILE **fp);
  121. extern int read_etc_hosts_r(FILE *fp, const char * name, int type,
  122. enum etc_hosts_action action,
  123. struct hostent * result_buf,
  124. char * buf, size_t buflen,
  125. struct hostent ** result,
  126. int * h_errnop);
  127. extern int resolve_address(const char * address, int nscount,
  128. char ** nsip, struct in_addr * in);
  129. extern int resolve_mailbox(const char * address, int nscount,
  130. char ** nsip, struct in_addr * in);
  131. extern int dns_lookup(const char * name, int type, int nscount,
  132. char ** nsip, unsigned char ** outpacket, struct resolv_answer * a);
  133. int encode_dotted(const char * dotted, unsigned char * dest, int maxlen);
  134. int decode_dotted(const unsigned char * message, int offset,
  135. char * dest, int maxlen);
  136. int length_dotted(const unsigned char * message, int offset);
  137. int encode_header(struct resolv_header * h, unsigned char * dest, int maxlen);
  138. int decode_header(unsigned char * data, struct resolv_header * h);
  139. int encode_question(struct resolv_question * q,
  140. unsigned char * dest, int maxlen);
  141. int decode_question(unsigned char * message, int offset,
  142. struct resolv_question * q);
  143. int encode_answer(struct resolv_answer * a,
  144. unsigned char * dest, int maxlen);
  145. int decode_answer(unsigned char * message, int offset,
  146. struct resolv_answer * a);
  147. int length_question(unsigned char * message, int offset);
  148. extern int open_nameservers(void);
  149. #ifdef L_encodeh
  150. int encode_header(struct resolv_header *h, unsigned char *dest, int maxlen)
  151. {
  152. if (maxlen < HFIXEDSZ)
  153. return -1;
  154. dest[0] = (h->id & 0xff00) >> 8;
  155. dest[1] = (h->id & 0x00ff) >> 0;
  156. dest[2] = (h->qr ? 0x80 : 0) |
  157. ((h->opcode & 0x0f) << 3) |
  158. (h->aa ? 0x04 : 0) |
  159. (h->tc ? 0x02 : 0) |
  160. (h->rd ? 0x01 : 0);
  161. dest[3] = (h->ra ? 0x80 : 0) | (h->rcode & 0x0f);
  162. dest[4] = (h->qdcount & 0xff00) >> 8;
  163. dest[5] = (h->qdcount & 0x00ff) >> 0;
  164. dest[6] = (h->ancount & 0xff00) >> 8;
  165. dest[7] = (h->ancount & 0x00ff) >> 0;
  166. dest[8] = (h->nscount & 0xff00) >> 8;
  167. dest[9] = (h->nscount & 0x00ff) >> 0;
  168. dest[10] = (h->arcount & 0xff00) >> 8;
  169. dest[11] = (h->arcount & 0x00ff) >> 0;
  170. return HFIXEDSZ;
  171. }
  172. #endif
  173. #ifdef L_decodeh
  174. int decode_header(unsigned char *data, struct resolv_header *h)
  175. {
  176. h->id = (data[0] << 8) | data[1];
  177. h->qr = (data[2] & 0x80) ? 1 : 0;
  178. h->opcode = (data[2] >> 3) & 0x0f;
  179. h->aa = (data[2] & 0x04) ? 1 : 0;
  180. h->tc = (data[2] & 0x02) ? 1 : 0;
  181. h->rd = (data[2] & 0x01) ? 1 : 0;
  182. h->ra = (data[3] & 0x80) ? 1 : 0;
  183. h->rcode = data[3] & 0x0f;
  184. h->qdcount = (data[4] << 8) | data[5];
  185. h->ancount = (data[6] << 8) | data[7];
  186. h->nscount = (data[8] << 8) | data[9];
  187. h->arcount = (data[10] << 8) | data[11];
  188. return HFIXEDSZ;
  189. }
  190. #endif
  191. #ifdef L_encoded
  192. /* Encode a dotted string into nameserver transport-level encoding.
  193. This routine is fairly dumb, and doesn't attempt to compress
  194. the data */
  195. int encode_dotted(const char *dotted, unsigned char *dest, int maxlen)
  196. {
  197. int used = 0;
  198. while (dotted && *dotted) {
  199. char *c = strchr(dotted, '.');
  200. int l = c ? c - dotted : strlen(dotted);
  201. if (l >= (maxlen - used - 1))
  202. return -1;
  203. dest[used++] = l;
  204. memcpy(dest + used, dotted, l);
  205. used += l;
  206. if (c)
  207. dotted = c + 1;
  208. else
  209. break;
  210. }
  211. if (maxlen < 1)
  212. return -1;
  213. dest[used++] = 0;
  214. return used;
  215. }
  216. #endif
  217. #ifdef L_decoded
  218. /* Decode a dotted string from nameserver transport-level encoding.
  219. This routine understands compressed data. */
  220. int decode_dotted(const unsigned char *data, int offset,
  221. char *dest, int maxlen)
  222. {
  223. int l;
  224. int measure = 1;
  225. int total = 0;
  226. int used = 0;
  227. if (!data)
  228. return -1;
  229. while ((l=data[offset++])) {
  230. if (measure)
  231. total++;
  232. if ((l & 0xc0) == (0xc0)) {
  233. if (measure)
  234. total++;
  235. /* compressed item, redirect */
  236. offset = ((l & 0x3f) << 8) | data[offset];
  237. measure = 0;
  238. continue;
  239. }
  240. if ((used + l + 1) >= maxlen)
  241. return -1;
  242. memcpy(dest + used, data + offset, l);
  243. offset += l;
  244. used += l;
  245. if (measure)
  246. total += l;
  247. if (data[offset] != 0)
  248. dest[used++] = '.';
  249. else
  250. dest[used++] = '\0';
  251. }
  252. DPRINTF("Total decode len = %d\n", total);
  253. return total;
  254. }
  255. #endif
  256. #ifdef L_lengthd
  257. int length_dotted(const unsigned char *data, int offset)
  258. {
  259. int orig_offset = offset;
  260. int l;
  261. if (!data)
  262. return -1;
  263. while ((l = data[offset++])) {
  264. if ((l & 0xc0) == (0xc0)) {
  265. offset++;
  266. break;
  267. }
  268. offset += l;
  269. }
  270. return offset - orig_offset;
  271. }
  272. #endif
  273. #ifdef L_encodeq
  274. int encode_question(struct resolv_question *q,
  275. unsigned char *dest, int maxlen)
  276. {
  277. int i;
  278. i = encode_dotted(q->dotted, dest, maxlen);
  279. if (i < 0)
  280. return i;
  281. dest += i;
  282. maxlen -= i;
  283. if (maxlen < 4)
  284. return -1;
  285. dest[0] = (q->qtype & 0xff00) >> 8;
  286. dest[1] = (q->qtype & 0x00ff) >> 0;
  287. dest[2] = (q->qclass & 0xff00) >> 8;
  288. dest[3] = (q->qclass & 0x00ff) >> 0;
  289. return i + 4;
  290. }
  291. #endif
  292. #ifdef L_decodeq
  293. int decode_question(unsigned char *message, int offset,
  294. struct resolv_question *q)
  295. {
  296. char temp[256];
  297. int i;
  298. i = decode_dotted(message, offset, temp, sizeof(temp));
  299. if (i < 0)
  300. return i;
  301. offset += i;
  302. q->dotted = strdup(temp);
  303. q->qtype = (message[offset + 0] << 8) | message[offset + 1];
  304. q->qclass = (message[offset + 2] << 8) | message[offset + 3];
  305. return i + 4;
  306. }
  307. #endif
  308. #ifdef L_lengthq
  309. int length_question(unsigned char *message, int offset)
  310. {
  311. int i;
  312. i = length_dotted(message, offset);
  313. if (i < 0)
  314. return i;
  315. return i + 4;
  316. }
  317. #endif
  318. #ifdef L_encodea
  319. int encode_answer(struct resolv_answer *a, unsigned char *dest, int maxlen)
  320. {
  321. int i;
  322. i = encode_dotted(a->dotted, dest, maxlen);
  323. if (i < 0)
  324. return i;
  325. dest += i;
  326. maxlen -= i;
  327. if (maxlen < (RRFIXEDSZ+a->rdlength))
  328. return -1;
  329. *dest++ = (a->atype & 0xff00) >> 8;
  330. *dest++ = (a->atype & 0x00ff) >> 0;
  331. *dest++ = (a->aclass & 0xff00) >> 8;
  332. *dest++ = (a->aclass & 0x00ff) >> 0;
  333. *dest++ = (a->ttl & 0xff000000) >> 24;
  334. *dest++ = (a->ttl & 0x00ff0000) >> 16;
  335. *dest++ = (a->ttl & 0x0000ff00) >> 8;
  336. *dest++ = (a->ttl & 0x000000ff) >> 0;
  337. *dest++ = (a->rdlength & 0xff00) >> 8;
  338. *dest++ = (a->rdlength & 0x00ff) >> 0;
  339. memcpy(dest, a->rdata, a->rdlength);
  340. return i + RRFIXEDSZ + a->rdlength;
  341. }
  342. #endif
  343. #ifdef L_decodea
  344. int decode_answer(unsigned char *message, int offset,
  345. struct resolv_answer *a)
  346. {
  347. char temp[256];
  348. int i;
  349. i = decode_dotted(message, offset, temp, sizeof(temp));
  350. if (i < 0)
  351. return i;
  352. message += offset + i;
  353. a->dotted = strdup(temp);
  354. a->atype = (message[0] << 8) | message[1];
  355. message += 2;
  356. a->aclass = (message[0] << 8) | message[1];
  357. message += 2;
  358. a->ttl = (message[0] << 24) |
  359. (message[1] << 16) | (message[2] << 8) | (message[3] << 0);
  360. message += 4;
  361. a->rdlength = (message[0] << 8) | message[1];
  362. message += 2;
  363. a->rdata = message;
  364. a->rdoffset = offset + i + RRFIXEDSZ;
  365. DPRINTF("i=%d,rdlength=%d\n", i, a->rdlength);
  366. return i + RRFIXEDSZ + a->rdlength;
  367. }
  368. #endif
  369. #ifdef L_encodep
  370. int encode_packet(struct resolv_header *h,
  371. struct resolv_question **q,
  372. struct resolv_answer **an,
  373. struct resolv_answer **ns,
  374. struct resolv_answer **ar,
  375. unsigned char *dest, int maxlen)
  376. {
  377. int i, total = 0;
  378. int j;
  379. i = encode_header(h, dest, maxlen);
  380. if (i < 0)
  381. return i;
  382. dest += i;
  383. maxlen -= i;
  384. total += i;
  385. for (j = 0; j < h->qdcount; j++) {
  386. i = encode_question(q[j], dest, maxlen);
  387. if (i < 0)
  388. return i;
  389. dest += i;
  390. maxlen -= i;
  391. total += i;
  392. }
  393. for (j = 0; j < h->ancount; j++) {
  394. i = encode_answer(an[j], dest, maxlen);
  395. if (i < 0)
  396. return i;
  397. dest += i;
  398. maxlen -= i;
  399. total += i;
  400. }
  401. for (j = 0; j < h->nscount; j++) {
  402. i = encode_answer(ns[j], dest, maxlen);
  403. if (i < 0)
  404. return i;
  405. dest += i;
  406. maxlen -= i;
  407. total += i;
  408. }
  409. for (j = 0; j < h->arcount; j++) {
  410. i = encode_answer(ar[j], dest, maxlen);
  411. if (i < 0)
  412. return i;
  413. dest += i;
  414. maxlen -= i;
  415. total += i;
  416. }
  417. return total;
  418. }
  419. #endif
  420. #ifdef L_decodep
  421. int decode_packet(unsigned char *data, struct resolv_header *h)
  422. {
  423. return decode_header(data, h);
  424. }
  425. #endif
  426. #ifdef L_formquery
  427. int form_query(int id, const char *name, int type, unsigned char *packet,
  428. int maxlen)
  429. {
  430. struct resolv_header h;
  431. struct resolv_question q;
  432. int i, j;
  433. memset(&h, 0, sizeof(h));
  434. h.id = id;
  435. h.qdcount = 1;
  436. q.dotted = (char *) name;
  437. q.qtype = type;
  438. q.qclass = C_IN; /* CLASS_IN */
  439. i = encode_header(&h, packet, maxlen);
  440. if (i < 0)
  441. return i;
  442. j = encode_question(&q, packet + i, maxlen - i);
  443. if (j < 0)
  444. return j;
  445. return i + j;
  446. }
  447. #endif
  448. #ifdef L_dnslookup
  449. int dns_caught_signal = 0;
  450. void dns_catch_signal(int signo)
  451. {
  452. dns_caught_signal = 1;
  453. }
  454. int dns_lookup(const char *name, int type, int nscount, char **nsip,
  455. unsigned char **outpacket, struct resolv_answer *a)
  456. {
  457. static int id = 1;
  458. int i, j, len, fd, pos;
  459. static int ns = 0;
  460. struct sockaddr_in sa;
  461. #ifdef __UCLIBC_HAS_IPV6__
  462. struct sockaddr_in6 sa6;
  463. #endif /* __UCLIBC_HAS_IPV6__ */
  464. int oldalarm;
  465. __sighandler_t oldhandler;
  466. struct resolv_header h;
  467. struct resolv_question q;
  468. int retries = 0;
  469. unsigned char * packet = malloc(PACKETSZ);
  470. char * lookup = malloc(MAXDNAME);
  471. int variant = 0;
  472. #ifdef __UCLIBC_HAS_IPV6__
  473. int v6;
  474. #endif /* __UCLIBC_HAS_IPV6__ */
  475. fd = -1;
  476. if (!packet || !lookup || !nscount)
  477. goto fail;
  478. DPRINTF("Looking up type %d answer for '%s'\n", type, name);
  479. ns %= nscount;
  480. while (retries++ < MAX_RETRIES) {
  481. #ifdef __UCLIBC_HAS_IPV6__
  482. v6 = (inet_pton(AF_INET6, nsip[ns], &sa6.sin6_addr) > 0);
  483. #endif /* __UCLIBC_HAS_IPV6__ */
  484. if (fd != -1)
  485. close(fd);
  486. #ifndef __UCLIBC_HAS_IPV6__
  487. fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
  488. #else /* __UCLIBC_HAS_IPV6__ */
  489. fd = socket(v6 ? AF_INET6 : AF_INET, SOCK_DGRAM, IPPROTO_UDP);
  490. #endif /* __UCLIBC_HAS_IPV6__ */
  491. if (fd == -1)
  492. goto fail;
  493. memset(packet, 0, PACKETSZ);
  494. memset(&h, 0, sizeof(h));
  495. h.id = ++id;
  496. h.qdcount = 1;
  497. h.rd = 1;
  498. DPRINTF("encoding header\n", h.rd);
  499. i = encode_header(&h, packet, PACKETSZ);
  500. if (i < 0)
  501. goto fail;
  502. strncpy(lookup,name,MAXDNAME);
  503. if (variant < searchdomains && strchr(lookup, '.') == NULL)
  504. {
  505. strncat(lookup,".", MAXDNAME);
  506. strncat(lookup,searchdomain[variant], MAXDNAME);
  507. }
  508. DPRINTF("lookup name: %s\n", lookup);
  509. q.dotted = (char *)lookup;
  510. q.qtype = type;
  511. q.qclass = C_IN; /* CLASS_IN */
  512. j = encode_question(&q, packet+i, PACKETSZ-i);
  513. if (j < 0)
  514. goto fail;
  515. len = i + j;
  516. DPRINTF("On try %d, sending query to port %d of machine %s\n",
  517. retries, NAMESERVER_PORT, nsip[ns]);
  518. #ifndef __UCLIBC_HAS_IPV6__
  519. sa.sin_family = AF_INET;
  520. sa.sin_port = htons(NAMESERVER_PORT);
  521. sa.sin_addr.s_addr = inet_addr(nsip[ns]);
  522. #else /* __UCLIBC_HAS_IPV6__ */
  523. if (v6) {
  524. sa6.sin6_family = AF_INET6;
  525. sa6.sin6_port = htons(NAMESERVER_PORT);
  526. /* sa6.sin6_addr is already here */
  527. } else {
  528. sa.sin_family = AF_INET;
  529. sa.sin_port = htons(NAMESERVER_PORT);
  530. sa.sin_addr.s_addr = inet_addr(nsip[ns]);
  531. }
  532. #endif /* __UCLIBC_HAS_IPV6__ */
  533. #ifndef __UCLIBC_HAS_IPV6__
  534. if (connect(fd, (struct sockaddr *) &sa, sizeof(sa)) == -1) {
  535. #else /* __UCLIBC_HAS_IPV6__ */
  536. if (connect(fd, (struct sockaddr *) (v6 ? &sa6 : &sa),
  537. v6 ? sizeof(sa6) : sizeof(sa)) == -1) {
  538. #endif /* __UCLIBC_HAS_IPV6__ */
  539. if (errno == ENETUNREACH) {
  540. /* routing error, presume not transient */
  541. goto tryall;
  542. } else
  543. /* retry */
  544. continue;
  545. }
  546. DPRINTF("Transmitting packet of length %d, id=%d, qr=%d\n",
  547. len, h.id, h.qr);
  548. send(fd, packet, len, 0);
  549. dns_caught_signal = 0;
  550. oldalarm = alarm(REPLY_TIMEOUT);
  551. oldhandler = signal(SIGALRM, dns_catch_signal);
  552. i = recv(fd, packet, PACKETSZ, 0);
  553. alarm(0);
  554. signal(SIGALRM, oldhandler);
  555. alarm(oldalarm);
  556. DPRINTF("Timeout=%d, len=%d\n", dns_caught_signal, i);
  557. if (dns_caught_signal)
  558. /* timed out, so retry send and receive,
  559. to next nameserver on queue */
  560. goto again;
  561. if (i < HFIXEDSZ)
  562. /* too short ! */
  563. goto again;
  564. decode_header(packet, &h);
  565. DPRINTF("id = %d, qr = %d\n", h.id, h.qr);
  566. if ((h.id != id) || (!h.qr))
  567. /* unsolicited */
  568. goto again;
  569. DPRINTF("Got response %s\n", "(i think)!");
  570. DPRINTF("qrcount=%d,ancount=%d,nscount=%d,arcount=%d\n",
  571. h.qdcount, h.ancount, h.nscount, h.arcount);
  572. DPRINTF("opcode=%d,aa=%d,tc=%d,rd=%d,ra=%d,rcode=%d\n",
  573. h.opcode, h.aa, h.tc, h.rd, h.ra, h.rcode);
  574. if ((h.rcode) || (h.ancount < 1)) {
  575. /* negative result, not present */
  576. goto again;
  577. }
  578. pos = HFIXEDSZ;
  579. for (j = 0; j < h.qdcount; j++) {
  580. DPRINTF("Skipping question %d at %d\n", j, pos);
  581. i = length_question(packet, pos);
  582. DPRINTF("Length of question %d is %d\n", j, i);
  583. if (i < 0)
  584. goto again;
  585. pos += i;
  586. }
  587. DPRINTF("Decoding answer at pos %d\n", pos);
  588. for (j=0;j<h.ancount;j++)
  589. {
  590. i = decode_answer(packet, pos, a);
  591. if (i<0) {
  592. DPRINTF("failed decode %d\n", i);
  593. goto again;
  594. }
  595. /* For all but T_SIG, accept first answer */
  596. if (a->atype != T_SIG)
  597. break;
  598. DPRINTF("skipping T_SIG %d\n", i);
  599. free(a->dotted);
  600. pos += i;
  601. }
  602. DPRINTF("Answer name = |%s|\n", a->dotted);
  603. DPRINTF("Answer type = |%d|\n", a->atype);
  604. close(fd);
  605. if (outpacket)
  606. *outpacket = packet;
  607. else
  608. free(packet);
  609. free(lookup);
  610. return (0); /* success! */
  611. tryall:
  612. /* if there are other nameservers, give them a go,
  613. otherwise return with error */
  614. variant = 0;
  615. if (retries >= nscount*(searchdomains+1))
  616. goto fail;
  617. again:
  618. /* if there are searchdomains, try them or fallback as passed */
  619. if (variant < searchdomains) {
  620. /* next search */
  621. variant++;
  622. } else {
  623. /* next server, first search */
  624. ns = (ns + 1) % nscount;
  625. variant = 0;
  626. }
  627. }
  628. fail:
  629. if (fd != -1)
  630. close(fd);
  631. if (lookup)
  632. free(lookup);
  633. if (packet)
  634. free(packet);
  635. return -1;
  636. }
  637. #endif
  638. #ifdef L_resolveaddress
  639. int resolve_address(const char *address, int nscount,
  640. char **nsip, struct in_addr *in)
  641. {
  642. unsigned char *packet;
  643. struct resolv_answer a;
  644. char temp[256];
  645. int i;
  646. int nest = 0;
  647. if (!address || !in)
  648. return -1;
  649. strncpy(temp, address, sizeof(temp));
  650. for (;;) {
  651. i = dns_lookup(temp, T_A, nscount, nsip, &packet, &a);
  652. if (i < 0)
  653. return -1;
  654. free(a.dotted);
  655. if (a.atype == T_CNAME) { /* CNAME */
  656. DPRINTF("Got a CNAME in resolve_address()\n");
  657. i = decode_dotted(packet, a.rdoffset, temp, sizeof(temp));
  658. free(packet);
  659. if (i < 0)
  660. return -1;
  661. if (++nest > MAX_RECURSE)
  662. return -1;
  663. continue;
  664. } else if (a.atype == T_A) { /* ADDRESS */
  665. free(packet);
  666. break;
  667. } else {
  668. free(packet);
  669. return -1;
  670. }
  671. }
  672. if (in)
  673. memcpy(in, a.rdata, INADDRSZ); /* IPv4 T_A */
  674. return 0;
  675. }
  676. #endif
  677. #ifdef L_resolvemailbox
  678. int resolve_mailbox(const char *address, int nscount,
  679. char **nsip, struct in_addr *in)
  680. {
  681. struct resolv_answer a;
  682. unsigned char *packet;
  683. char temp[256];
  684. int nest = 0;
  685. int i;
  686. if (!address || !in)
  687. return -1;
  688. /* look up mail exchange */
  689. i = dns_lookup(address, T_MX, nscount, nsip, &packet, &a);
  690. strncpy(temp, address, sizeof(temp));
  691. if (i >= 0) {
  692. i = decode_dotted(packet, a.rdoffset+2, temp, sizeof(temp));
  693. free(packet);
  694. }
  695. for (;;) {
  696. i = dns_lookup(temp, T_A, nscount, nsip, &packet, &a);
  697. if (i < 0)
  698. return -1;
  699. free(a.dotted);
  700. if (a.atype == T_CNAME) { /* CNAME */
  701. DPRINTF("Got a CNAME in resolve_mailbox()\n");
  702. i = decode_dotted(packet, a.rdoffset, temp, sizeof(temp));
  703. free(packet);
  704. if (i < 0)
  705. return i;
  706. if (++nest > MAX_RECURSE)
  707. return -1;
  708. continue;
  709. } else if (a.atype == T_A) { /* ADDRESS */
  710. free(packet);
  711. break;
  712. } else {
  713. free(packet);
  714. return -1;
  715. }
  716. }
  717. if (in)
  718. memcpy(in, a.rdata, INADDRSZ); /* IPv4 */
  719. return 0;
  720. }
  721. #endif
  722. #ifdef L_opennameservers
  723. int nameservers;
  724. char * nameserver[MAX_SERVERS];
  725. int searchdomains;
  726. char * searchdomain[MAX_SEARCH];
  727. /*
  728. * we currently read formats not quite the same as that on normal
  729. * unix systems, we can have a list of nameservers after the keyword.
  730. */
  731. int open_nameservers()
  732. {
  733. FILE *fp;
  734. int i;
  735. #define RESOLV_ARGS 5
  736. char szBuffer[128], *p, *argv[RESOLV_ARGS];
  737. int argc;
  738. if (nameservers > 0)
  739. return 0;
  740. if ((fp = fopen("/etc/resolv.conf", "r")) ||
  741. (fp = fopen("/etc/config/resolv.conf", "r"))) {
  742. while (fgets(szBuffer, sizeof(szBuffer), fp) != NULL) {
  743. for (p = szBuffer; *p && isspace(*p); p++)
  744. /* skip white space */;
  745. if (*p == '\0' || *p == '\n' || *p == '#') /* skip comments etc */
  746. continue;
  747. argc = 0;
  748. while (*p && argc < RESOLV_ARGS) {
  749. argv[argc++] = p;
  750. while (*p && !isspace(*p) && *p != '\n')
  751. p++;
  752. while (*p && (isspace(*p) || *p == '\n')) /* remove spaces */
  753. *p++ = '\0';
  754. }
  755. if (strcmp(argv[0], "nameserver") == 0) {
  756. for (i = 1; i < argc && nameservers < MAX_SERVERS; i++) {
  757. nameserver[nameservers++] = strdup(argv[i]);
  758. DPRINTF("adding nameserver %s\n", argv[i]);
  759. }
  760. }
  761. /* domain and search are mutually exclusive, the last one wins */
  762. if (strcmp(argv[0],"domain")==0 || strcmp(argv[0],"search")==0) {
  763. while (searchdomains > 0) {
  764. free(searchdomain[--searchdomains]);
  765. searchdomain[searchdomains] = NULL;
  766. }
  767. for (i=1; i < argc && searchdomains < MAX_SEARCH; i++) {
  768. searchdomain[searchdomains++] = strdup(argv[i]);
  769. DPRINTF("adding search %s\n", argv[i]);
  770. }
  771. }
  772. }
  773. fclose(fp);
  774. } else {
  775. DPRINTF("failed to open %s\n", "resolv.conf");
  776. }
  777. DPRINTF("nameservers = %d\n", nameservers);
  778. return 0;
  779. }
  780. #endif
  781. #ifdef L_closenameservers
  782. void close_nameservers(void)
  783. {
  784. while (nameservers > 0) {
  785. free(nameserver[--nameservers]);
  786. nameserver[nameservers] = NULL;
  787. }
  788. while (searchdomains > 0) {
  789. free(searchdomain[--searchdomains]);
  790. searchdomain[searchdomains] = NULL;
  791. }
  792. }
  793. #endif
  794. #ifdef L_resolvename
  795. const char *resolve_name(const char *name, int mailbox)
  796. {
  797. struct in_addr in;
  798. int i;
  799. /* shortcut: is it a valid IP address to begin with? */
  800. if (inet_aton(name, &in))
  801. return name;
  802. open_nameservers();
  803. DPRINTF("looking up '%s', mailbox=%d, nameservers=%d\n",
  804. name, mailbox, nameservers);
  805. if (mailbox)
  806. i = resolve_mailbox(name, nameservers, nameserver, &in);
  807. else
  808. i = resolve_address(name, nameservers, nameserver, &in);
  809. if (i < 0)
  810. return 0;
  811. DPRINTF("success = '%s'\n", inet_ntoa(in));
  812. return inet_ntoa(in);
  813. }
  814. #endif
  815. #ifdef L_gethostbyname
  816. struct hostent *gethostbyname(const char *name)
  817. {
  818. static struct hostent h;
  819. static char buf[sizeof(struct in_addr) +
  820. sizeof(struct in_addr *)*2 +
  821. 256/*namebuffer*/ + 32/* margin */];
  822. struct hostent *hp;
  823. gethostbyname_r(name, &h, buf, sizeof(buf), &hp, &h_errno);
  824. return hp;
  825. }
  826. #endif
  827. #ifdef L_gethostbyname2
  828. #ifdef __UCLIBC_HAS_IPV6__
  829. /* TBD: Not the right place for defining these, I guess */
  830. const struct in6_addr in6addr_any =
  831. { { { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } } };
  832. const struct in6_addr in6addr_loopback =
  833. { { { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1 } } };
  834. #endif /* __UCLIBC_HAS_IPV6__ */
  835. struct hostent *gethostbyname2(const char *name, int family)
  836. {
  837. #ifndef __UCLIBC_HAS_IPV6__
  838. return family == AF_INET ? gethostbyname(name) : (struct hostent*)0;
  839. #else /* __UCLIBC_HAS_IPV6__ */
  840. static struct hostent h;
  841. static char buf[sizeof(struct in6_addr) +
  842. sizeof(struct in6_addr *)*2 +
  843. 256/*namebuffer*/ + 32/* margin */];
  844. struct hostent *hp;
  845. gethostbyname_r(name, &h, buf, sizeof(buf), &hp, &h_errno);
  846. return hp;
  847. #endif /* __UCLIBC_HAS_IPV6__ */
  848. }
  849. #endif
  850. #ifdef L_getnetbyname
  851. struct netent * getnetbyname(const char * name)
  852. {
  853. return NULL;
  854. }
  855. #endif
  856. #ifdef L_res_init
  857. int res_init(void)
  858. {
  859. return(0);
  860. }
  861. #endif
  862. #ifdef L_res_query
  863. #ifndef MIN
  864. #define MIN(x, y) ((x) < (y) ? (x) : (y))
  865. #endif
  866. int res_query(const char *dname, int class, int type,
  867. unsigned char *answer, int anslen)
  868. {
  869. unsigned char * packet = 0;
  870. struct resolv_answer a;
  871. int i;
  872. open_nameservers();
  873. if (!dname || class != 1 /* CLASS_IN */)
  874. return(-1);
  875. memset((char *) &a, '\0', sizeof(a));
  876. i = dns_lookup(dname, type, nameservers, nameserver, &packet, &a);
  877. if (i < 0)
  878. return(-1);
  879. free(a.dotted);
  880. if (a.atype == type) { /* CNAME*/
  881. if (anslen && answer)
  882. memcpy(answer, a.rdata, MIN(anslen, a.rdlength));
  883. if (packet)
  884. free(packet);
  885. return(MIN(anslen, a.rdlength));
  886. }
  887. if (packet)
  888. free(packet);
  889. return 0;
  890. }
  891. #endif
  892. #ifdef L_gethostbyaddr
  893. struct hostent *gethostbyaddr (const void *addr, socklen_t len, int type)
  894. {
  895. static struct hostent h;
  896. static char buf[
  897. #ifndef __UCLIBC_HAS_IPV6__
  898. sizeof(struct in_addr) + sizeof(struct in_addr *)*2 +
  899. #else
  900. sizeof(struct in6_addr) + sizeof(struct in6_addr *)*2 +
  901. #endif /* __UCLIBC_HAS_IPV6__ */
  902. 256/*namebuffer*/ + 32/* margin */];
  903. struct hostent *hp;
  904. gethostbyaddr_r(addr, len, type, &h, buf, sizeof(buf), &hp, &h_errno);
  905. return hp;
  906. }
  907. #endif
  908. #ifdef L_read_etc_hosts_r
  909. void __open_etc_hosts(FILE **fp)
  910. {
  911. if ((*fp = fopen("/etc/hosts", "r")) == NULL) {
  912. *fp = fopen("/etc/config/hosts", "r");
  913. }
  914. return;
  915. }
  916. int read_etc_hosts_r(FILE * fp, const char * name, int type,
  917. enum etc_hosts_action action,
  918. struct hostent * result_buf,
  919. char * buf, size_t buflen,
  920. struct hostent ** result,
  921. int * h_errnop)
  922. {
  923. struct in_addr *in=NULL;
  924. struct in_addr **addr_list=NULL;
  925. #ifdef __UCLIBC_HAS_IPV6__
  926. struct in6_addr *in6=NULL;
  927. struct in6_addr **addr_list6=NULL;
  928. #endif /* __UCLIBC_HAS_IPV6__ */
  929. char *cp;
  930. #define MAX_ALIAS 5
  931. char *alias[MAX_ALIAS];
  932. int aliases, i;
  933. int ret=HOST_NOT_FOUND;
  934. if (action!=GETHOSTENT) {
  935. #ifdef __UCLIBC_HAS_IPV6__
  936. char *p=buf;
  937. size_t len=buflen;
  938. #endif /* __UCLIBC_HAS_IPV6__ */
  939. *h_errnop=NETDB_INTERNAL;
  940. if (buflen < sizeof(*in))
  941. return ERANGE;
  942. in=(struct in_addr*)buf;
  943. buf+=sizeof(*in);
  944. buflen-=sizeof(*in);
  945. if (buflen < sizeof(*addr_list)*2)
  946. return ERANGE;
  947. addr_list=(struct in_addr **)buf;
  948. buf+=sizeof(*addr_list)*2;
  949. buflen-=sizeof(*addr_list)*2;
  950. #ifdef __UCLIBC_HAS_IPV6__
  951. if (len < sizeof(*in6))
  952. return ERANGE;
  953. in6=(struct in6_addr*)p;
  954. p+=sizeof(*in6);
  955. len-=sizeof(*in6);
  956. if (len < sizeof(*addr_list6)*2)
  957. return ERANGE;
  958. addr_list6=(struct in6_addr**)p;
  959. p+=sizeof(*addr_list6)*2;
  960. len-=sizeof(*addr_list6)*2;
  961. if (len < buflen) {
  962. buflen=len;
  963. buf=p;
  964. }
  965. #endif /* __UCLIBC_HAS_IPV6__ */
  966. if (buflen < 80)
  967. return ERANGE;
  968. __open_etc_hosts(&fp);
  969. if (fp == NULL) {
  970. result=NULL;
  971. return errno;
  972. }
  973. }
  974. *h_errnop=HOST_NOT_FOUND;
  975. while (fgets(buf, buflen, fp)) {
  976. if ((cp = strchr(buf, '#')))
  977. *cp = '\0';
  978. DPRINTF("Looking at: %s\n", buf);
  979. aliases = 0;
  980. cp = buf;
  981. while (*cp) {
  982. while (*cp && isspace(*cp))
  983. *cp++ = '\0';
  984. if (!*cp)
  985. continue;
  986. if (aliases < MAX_ALIAS)
  987. alias[aliases++] = cp;
  988. while (*cp && !isspace(*cp))
  989. cp++;
  990. }
  991. if (aliases < 2)
  992. continue; /* syntax error really */
  993. if (action==GETHOSTENT) {
  994. /* Return whatever the next entry happens to be. */
  995. break;
  996. } else if (action==GET_HOSTS_BYADDR) {
  997. if (strcmp(name, alias[0]) != 0)
  998. continue;
  999. } else {
  1000. /* GET_HOSTS_BYNAME */
  1001. for (i = 1; i < aliases; i++)
  1002. if (strcasecmp(name, alias[i]) == 0)
  1003. break;
  1004. if (i >= aliases)
  1005. continue;
  1006. }
  1007. if (type == AF_INET && inet_pton(AF_INET, alias[0], in) > 0) {
  1008. DPRINTF("Found INET\n");
  1009. addr_list[0] = in;
  1010. addr_list[1] = 0;
  1011. result_buf->h_name = alias[1];
  1012. result_buf->h_addrtype = AF_INET;
  1013. result_buf->h_length = sizeof(*in);
  1014. result_buf->h_addr_list = (char**) addr_list;
  1015. *result=result_buf;
  1016. ret=NETDB_SUCCESS;
  1017. #ifdef __UCLIBC_HAS_IPV6__
  1018. } else if (type == AF_INET6 && inet_pton(AF_INET6, alias[0], in6) > 0) {
  1019. DPRINTF("Found INET6\n");
  1020. addr_list6[0] = in6;
  1021. addr_list6[1] = 0;
  1022. result_buf->h_name = alias[1];
  1023. result_buf->h_addrtype = AF_INET6;
  1024. result_buf->h_length = sizeof(*in6);
  1025. result_buf->h_addr_list = (char**) addr_list6;
  1026. *result=result_buf;
  1027. ret=NETDB_SUCCESS;
  1028. #endif /* __UCLIBC_HAS_IPV6__ */
  1029. } else {
  1030. DPRINTF("Error\n");
  1031. ret=TRY_AGAIN;
  1032. break; /* bad ip address */
  1033. }
  1034. if (action!=GETHOSTENT) {
  1035. fclose(fp);
  1036. }
  1037. return ret;
  1038. }
  1039. if (action!=GETHOSTENT) {
  1040. fclose(fp);
  1041. }
  1042. return ret;
  1043. }
  1044. #endif
  1045. #ifdef L_endhostent
  1046. extern int __stay_open;
  1047. extern FILE * __gethostent_fp;
  1048. void endhostent (void)
  1049. {
  1050. __stay_open = 0;
  1051. if (__gethostent_fp) {
  1052. fclose(__gethostent_fp);
  1053. }
  1054. }
  1055. #endif
  1056. #ifdef L_sethostent
  1057. extern int __stay_open;
  1058. void sethostent (int stay_open)
  1059. {
  1060. __stay_open = stay_open;
  1061. }
  1062. #endif
  1063. #ifdef L_gethostent
  1064. int __stay_open;
  1065. FILE * __gethostent_fp;
  1066. struct hostent *gethostent (void)
  1067. {
  1068. static struct hostent h;
  1069. static char buf[
  1070. #ifndef __UCLIBC_HAS_IPV6__
  1071. sizeof(struct in_addr) + sizeof(struct in_addr *)*2 +
  1072. #else
  1073. sizeof(struct in6_addr) + sizeof(struct in6_addr *)*2 +
  1074. #endif /* __UCLIBC_HAS_IPV6__ */
  1075. 80/*namebuffer*/ + 2/* margin */];
  1076. struct hostent *host;
  1077. if (__gethostent_fp == NULL) {
  1078. __open_etc_hosts(&__gethostent_fp);
  1079. if (__gethostent_fp == NULL) {
  1080. return((struct hostent *)NULL);
  1081. }
  1082. }
  1083. read_etc_hosts_r(__gethostent_fp, NULL, AF_INET, GETHOSTENT,
  1084. &h, buf, sizeof(buf), &host, &h_errno);
  1085. if (__stay_open==0) {
  1086. fclose(__gethostent_fp);
  1087. }
  1088. return(host);
  1089. }
  1090. #endif
  1091. #ifdef L_get_hosts_byname_r
  1092. int get_hosts_byname_r(const char * name, int type,
  1093. struct hostent * result_buf,
  1094. char * buf, size_t buflen,
  1095. struct hostent ** result,
  1096. int * h_errnop)
  1097. {
  1098. return(read_etc_hosts_r(NULL, name, type, GET_HOSTS_BYNAME, result_buf, buf, buflen, result, h_errnop));
  1099. }
  1100. #endif
  1101. #ifdef L_get_hosts_byaddr_r
  1102. int get_hosts_byaddr_r(const char * addr, int len, int type,
  1103. struct hostent * result_buf,
  1104. char * buf, size_t buflen,
  1105. struct hostent ** result,
  1106. int * h_errnop)
  1107. {
  1108. #ifndef __UCLIBC_HAS_IPV6__
  1109. char ipaddr[INET_ADDRSTRLEN];
  1110. #else
  1111. char ipaddr[INET6_ADDRSTRLEN];
  1112. #endif /* __UCLIBC_HAS_IPV6__ */
  1113. switch (type) {
  1114. case AF_INET:
  1115. if (len != sizeof(struct in_addr))
  1116. return 0;
  1117. break;
  1118. #ifdef __UCLIBC_HAS_IPV6__
  1119. case AF_INET6:
  1120. if (len != sizeof(struct in6_addr))
  1121. return 0;
  1122. break;
  1123. #endif /* __UCLIBC_HAS_IPV6__ */
  1124. default:
  1125. return 0;
  1126. }
  1127. inet_ntop(type, addr, ipaddr, sizeof(ipaddr));
  1128. return(read_etc_hosts_r(NULL, ipaddr, type, GET_HOSTS_BYADDR, result_buf, buf, buflen, result, h_errnop));
  1129. }
  1130. #endif
  1131. #ifdef L_getnameinfo
  1132. #ifndef min
  1133. # define min(x,y) (((x) > (y)) ? (y) : (x))
  1134. #endif /* min */
  1135. int getnameinfo (const struct sockaddr *sa, socklen_t addrlen, char *host,
  1136. socklen_t hostlen, char *serv, socklen_t servlen,
  1137. unsigned int flags)
  1138. {
  1139. int serrno = errno;
  1140. int ok = 0;
  1141. struct hostent *h = NULL;
  1142. char domain[256];
  1143. if (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV|NI_NOFQDN|NI_NAMEREQD|NI_DGRAM))
  1144. return EAI_BADFLAGS;
  1145. if (sa == NULL || addrlen < sizeof (sa_family_t))
  1146. return EAI_FAMILY;
  1147. switch (sa->sa_family) {
  1148. case AF_LOCAL:
  1149. break;
  1150. case AF_INET:
  1151. if (addrlen < sizeof (struct sockaddr_in))
  1152. return EAI_FAMILY;
  1153. break;
  1154. #ifdef __UCLIBC_HAS_IPV6__
  1155. case AF_INET6:
  1156. if (addrlen < sizeof (struct sockaddr_in6))
  1157. return EAI_FAMILY;
  1158. break;
  1159. #endif /* __UCLIBC_HAS_IPV6__ */
  1160. default:
  1161. return EAI_FAMILY;
  1162. }
  1163. if (host != NULL && hostlen > 0)
  1164. switch (sa->sa_family) {
  1165. case AF_INET:
  1166. #ifdef __UCLIBC_HAS_IPV6__
  1167. case AF_INET6:
  1168. #endif /* __UCLIBC_HAS_IPV6__ */
  1169. if (!(flags & NI_NUMERICHOST)) {
  1170. #ifdef __UCLIBC_HAS_IPV6__
  1171. if (sa->sa_family == AF_INET6)
  1172. h = gethostbyaddr ((const void *) &(((const struct sockaddr_in6 *) sa)->sin6_addr),
  1173. sizeof(struct in6_addr), AF_INET6);
  1174. else
  1175. #endif /* __UCLIBC_HAS_IPV6__ */
  1176. h = gethostbyaddr ((const void *) &(((const struct sockaddr_in *)sa)->sin_addr),
  1177. sizeof(struct in_addr), AF_INET);
  1178. if (h) {
  1179. char *c;
  1180. if ((flags & NI_NOFQDN)
  1181. && (getdomainname (domain, sizeof(domain)) == 0)
  1182. && (c = strstr (h->h_name, domain))
  1183. && (c != h->h_name) && (*(--c) == '.')) {
  1184. strncpy (host, h->h_name,
  1185. min(hostlen, (size_t) (c - h->h_name)));
  1186. host[min(hostlen - 1, (size_t) (c - h->h_name))] = '\0';
  1187. ok = 1;
  1188. } else {
  1189. strncpy (host, h->h_name, hostlen);
  1190. ok = 1;
  1191. }
  1192. }
  1193. }
  1194. if (!ok) {
  1195. if (flags & NI_NAMEREQD) {
  1196. errno = serrno;
  1197. return EAI_NONAME;
  1198. } else {
  1199. const char *c;
  1200. #ifdef __UCLIBC_HAS_IPV6__
  1201. if (sa->sa_family == AF_INET6) {
  1202. const struct sockaddr_in6 *sin6p;
  1203. sin6p = (const struct sockaddr_in6 *) sa;
  1204. c = inet_ntop (AF_INET6,
  1205. (const void *) &sin6p->sin6_addr, host, hostlen);
  1206. #if 0
  1207. /* Does scope id need to be supported? */
  1208. uint32_t scopeid;
  1209. scopeid = sin6p->sin6_scope_id;
  1210. if (scopeid != 0) {
  1211. /* Buffer is >= IFNAMSIZ+1. */
  1212. char scopebuf[IFNAMSIZ + 1];
  1213. char *scopeptr;
  1214. int ni_numericscope = 0;
  1215. size_t real_hostlen = __strnlen (host, hostlen);
  1216. size_t scopelen = 0;
  1217. scopebuf[0] = SCOPE_DELIMITER;
  1218. scopebuf[1] = '\0';
  1219. scopeptr = &scopebuf[1];
  1220. if (IN6_IS_ADDR_LINKLOCAL (&sin6p->sin6_addr)
  1221. || IN6_IS_ADDR_MC_LINKLOCAL (&sin6p->sin6_addr)) {
  1222. if (if_indextoname (scopeid, scopeptr) == NULL)
  1223. ++ni_numericscope;
  1224. else
  1225. scopelen = strlen (scopebuf);
  1226. } else {
  1227. ++ni_numericscope;
  1228. }
  1229. if (ni_numericscope)
  1230. scopelen = 1 + snprintf (scopeptr,
  1231. (scopebuf
  1232. + sizeof scopebuf
  1233. - scopeptr),
  1234. "%u", scopeid);
  1235. if (real_hostlen + scopelen + 1 > hostlen)
  1236. return EAI_SYSTEM;
  1237. memcpy (host + real_hostlen, scopebuf, scopelen + 1);
  1238. }
  1239. #endif
  1240. } else
  1241. #endif /* __UCLIBC_HAS_IPV6__ */
  1242. c = inet_ntop (AF_INET,
  1243. (const void *) &(((const struct sockaddr_in *) sa)->sin_addr),
  1244. host, hostlen);
  1245. if (c == NULL) {
  1246. errno = serrno;
  1247. return EAI_SYSTEM;
  1248. }
  1249. }
  1250. ok = 1;
  1251. }
  1252. break;
  1253. case AF_LOCAL:
  1254. if (!(flags & NI_NUMERICHOST)) {
  1255. struct utsname utsname;
  1256. if (!uname (&utsname)) {
  1257. strncpy (host, utsname.nodename, hostlen);
  1258. break;
  1259. };
  1260. };
  1261. if (flags & NI_NAMEREQD) {
  1262. errno = serrno;
  1263. return EAI_NONAME;
  1264. }
  1265. strncpy (host, "localhost", hostlen);
  1266. break;
  1267. default:
  1268. return EAI_FAMILY;
  1269. }
  1270. if (serv && (servlen > 0)) {
  1271. switch (sa->sa_family) {
  1272. case AF_INET:
  1273. #ifdef __UCLIBC_HAS_IPV6__
  1274. case AF_INET6:
  1275. #endif /* __UCLIBC_HAS_IPV6__ */
  1276. if (!(flags & NI_NUMERICSERV)) {
  1277. struct servent *s;
  1278. s = getservbyport (((const struct sockaddr_in *) sa)->sin_port,
  1279. ((flags & NI_DGRAM) ? "udp" : "tcp"));
  1280. if (s) {
  1281. strncpy (serv, s->s_name, servlen);
  1282. break;
  1283. }
  1284. }
  1285. snprintf (serv, servlen, "%d",
  1286. ntohs (((const struct sockaddr_in *) sa)->sin_port));
  1287. break;
  1288. case AF_LOCAL:
  1289. strncpy (serv, ((const struct sockaddr_un *) sa)->sun_path, servlen);
  1290. break;
  1291. }
  1292. }
  1293. if (host && (hostlen > 0))
  1294. host[hostlen-1] = 0;
  1295. if (serv && (servlen > 0))
  1296. serv[servlen-1] = 0;
  1297. errno = serrno;
  1298. return 0;
  1299. }
  1300. #endif
  1301. #ifdef L_gethostbyname_r
  1302. int gethostbyname_r(const char * name,
  1303. struct hostent * result_buf,
  1304. char * buf, size_t buflen,
  1305. struct hostent ** result,
  1306. int * h_errnop)
  1307. {
  1308. struct in_addr *in;
  1309. struct in_addr **addr_list;
  1310. unsigned char *packet;
  1311. struct resolv_answer a;
  1312. int i;
  1313. int nest = 0;
  1314. open_nameservers();
  1315. *result=NULL;
  1316. if (!name)
  1317. return EINVAL;
  1318. /* do /etc/hosts first */
  1319. if ((i=get_hosts_byname_r(name, AF_INET, result_buf,
  1320. buf, buflen, result, h_errnop))==0)
  1321. return i;
  1322. switch (*h_errnop) {
  1323. case HOST_NOT_FOUND:
  1324. case NO_ADDRESS:
  1325. break;
  1326. default:
  1327. return i;
  1328. }
  1329. DPRINTF("Nothing found in /etc/hosts\n");
  1330. *h_errnop = NETDB_INTERNAL;
  1331. if (buflen < sizeof(*in))
  1332. return ERANGE;
  1333. in=(struct in_addr*)buf;
  1334. buf+=sizeof(*in);
  1335. buflen-=sizeof(*in);
  1336. if (buflen < sizeof(*addr_list)*2)
  1337. return ERANGE;
  1338. addr_list=(struct in_addr**)buf;
  1339. buf+=sizeof(*addr_list)*2;
  1340. buflen-=sizeof(*addr_list)*2;
  1341. addr_list[0] = in;
  1342. addr_list[1] = 0;
  1343. if (buflen<256)
  1344. return ERANGE;
  1345. strncpy(buf, name, buflen);
  1346. /* First check if this is already an address */
  1347. if (inet_aton(name, in)) {
  1348. result_buf->h_name = buf;
  1349. result_buf->h_addrtype = AF_INET;
  1350. result_buf->h_length = sizeof(*in);
  1351. result_buf->h_addr_list = (char **) addr_list;
  1352. *h_errnop = NETDB_SUCCESS;
  1353. return NETDB_SUCCESS;
  1354. }
  1355. for (;;) {
  1356. i = dns_lookup(buf, T_A, nameservers, nameserver, &packet, &a);
  1357. if (i < 0) {
  1358. *h_errnop = HOST_NOT_FOUND;
  1359. DPRINTF("dns_lookup\n");
  1360. return TRY_AGAIN;
  1361. }
  1362. strncpy(buf, a.dotted, buflen);
  1363. free(a.dotted);
  1364. if (a.atype == T_CNAME) { /* CNAME */
  1365. DPRINTF("Got a CNAME in gethostbyname()\n");
  1366. i = decode_dotted(packet, a.rdoffset, buf, buflen);
  1367. free(packet);
  1368. if (i < 0) {
  1369. *h_errnop = NO_RECOVERY;
  1370. DPRINTF("decode_dotted\n");
  1371. return -1;
  1372. }
  1373. if (++nest > MAX_RECURSE) {
  1374. *h_errnop = NO_RECOVERY;
  1375. DPRINTF("recursion\n");
  1376. return -1;
  1377. }
  1378. continue;
  1379. } else if (a.atype == T_A) { /* ADDRESS */
  1380. memcpy(in, a.rdata, sizeof(*in));
  1381. result_buf->h_name = buf;
  1382. result_buf->h_addrtype = AF_INET;
  1383. result_buf->h_length = sizeof(*in);
  1384. result_buf->h_addr_list = (char **) addr_list;
  1385. free(packet);
  1386. break;
  1387. } else {
  1388. free(packet);
  1389. *h_errnop=HOST_NOT_FOUND;
  1390. return TRY_AGAIN;
  1391. }
  1392. }
  1393. *result=result_buf;
  1394. return NETDB_SUCCESS;
  1395. }
  1396. #endif
  1397. #ifdef L_gethostbyname2_r
  1398. #ifdef __UCLIBC_HAS_IPV6__
  1399. /* TBD: Not the right place for defining these, I guess */
  1400. /*
  1401. const struct in6_addr in6addr_any =
  1402. { { { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } } };
  1403. const struct in6_addr in6addr_loopback =
  1404. { { { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1 } } };
  1405. */
  1406. #endif /* __UCLIBC_HAS_IPV6__ */
  1407. int gethostbyname2_r(const char *name, int family,
  1408. struct hostent * result_buf,
  1409. char * buf, size_t buflen,
  1410. struct hostent ** result,
  1411. int * h_errnop)
  1412. {
  1413. #ifndef __UCLIBC_HAS_IPV6__
  1414. return family == AF_INET ? gethostbyname_r(name, result_buf, buf, buflen, result, h_errnop) : HOST_NOT_FOUND;
  1415. #else /* __UCLIBC_HAS_IPV6__ */
  1416. struct in6_addr *in;
  1417. struct in6_addr **addr_list;
  1418. unsigned char *packet;
  1419. struct resolv_answer a;
  1420. int i;
  1421. int nest = 0;
  1422. if (family == AF_INET)
  1423. return gethostbyname_r(name, result_buf, buf, buflen, result, h_errnop);
  1424. if (family != AF_INET6)
  1425. return EINVAL;
  1426. open_nameservers();
  1427. *result=NULL;
  1428. if (!name)
  1429. return EINVAL;
  1430. /* do /etc/hosts first */
  1431. if ((i=get_hosts_byname_r(name, family, result_buf,
  1432. buf, buflen, result, h_errnop))==0)
  1433. return i;
  1434. switch (*h_errnop) {
  1435. case HOST_NOT_FOUND:
  1436. case NO_ADDRESS:
  1437. break;
  1438. default:
  1439. return i;
  1440. }
  1441. DPRINTF("Nothing found in /etc/hosts\n");
  1442. *h_errnop = NETDB_INTERNAL;
  1443. if (buflen < sizeof(*in))
  1444. return ERANGE;
  1445. in=(struct in6_addr*)buf;
  1446. buf+=sizeof(*in);
  1447. buflen-=sizeof(*in);
  1448. if (buflen < sizeof(*addr_list)*2)
  1449. return ERANGE;
  1450. addr_list=(struct in6_addr**)buf;
  1451. buf+=sizeof(*addr_list)*2;
  1452. buflen-=sizeof(*addr_list)*2;
  1453. addr_list[0] = in;
  1454. addr_list[1] = 0;
  1455. if (buflen<256)
  1456. return ERANGE;
  1457. strncpy(buf, name, buflen);
  1458. /* First check if this is already an address */
  1459. if (inet_pton(AF_INET6, name, in)) {
  1460. result_buf->h_name = buf;
  1461. result_buf->h_addrtype = AF_INET6;
  1462. result_buf->h_length = sizeof(*in);
  1463. result_buf->h_addr_list = (char **) addr_list;
  1464. *h_errnop = NETDB_SUCCESS;
  1465. return NETDB_SUCCESS;
  1466. }
  1467. for (;;) {
  1468. i = dns_lookup(buf, T_AAAA, nameservers, nameserver, &packet, &a);
  1469. if (i < 0) {
  1470. *h_errnop = HOST_NOT_FOUND;
  1471. return TRY_AGAIN;
  1472. }
  1473. strncpy(buf, a.dotted, buflen);
  1474. free(a.dotted);
  1475. if (a.atype == T_CNAME) { /* CNAME */
  1476. DPRINTF("Got a CNAME in gethostbyname()\n");
  1477. i = decode_dotted(packet, a.rdoffset, buf, buflen);
  1478. free(packet);
  1479. if (i < 0) {
  1480. *h_errnop = NO_RECOVERY;
  1481. return -1;
  1482. }
  1483. if (++nest > MAX_RECURSE) {
  1484. *h_errnop = NO_RECOVERY;
  1485. return -1;
  1486. }
  1487. continue;
  1488. } else if (a.atype == T_AAAA) { /* ADDRESS */
  1489. memcpy(in, a.rdata, sizeof(*in));
  1490. result_buf->h_name = buf;
  1491. result_buf->h_addrtype = AF_INET6;
  1492. result_buf->h_length = sizeof(*in);
  1493. result_buf->h_addr_list = (char **) addr_list;
  1494. free(packet);
  1495. break;
  1496. } else {
  1497. free(packet);
  1498. *h_errnop=HOST_NOT_FOUND;
  1499. return TRY_AGAIN;
  1500. }
  1501. }
  1502. *result=result_buf;
  1503. return NETDB_SUCCESS;
  1504. #endif /* __UCLIBC_HAS_IPV6__ */
  1505. }
  1506. #endif
  1507. #ifdef L_gethostbyaddr_r
  1508. int gethostbyaddr_r (const void *addr, socklen_t len, int type,
  1509. struct hostent * result_buf,
  1510. char * buf, size_t buflen,
  1511. struct hostent ** result,
  1512. int * h_errnop)
  1513. {
  1514. struct in_addr *in;
  1515. struct in_addr **addr_list;
  1516. #ifdef __UCLIBC_HAS_IPV6__
  1517. char *qp;
  1518. size_t plen;
  1519. struct in6_addr *in6;
  1520. struct in6_addr **addr_list6;
  1521. #endif /* __UCLIBC_HAS_IPV6__ */
  1522. unsigned char *packet;
  1523. struct resolv_answer a;
  1524. int i;
  1525. int nest = 0;
  1526. *result=NULL;
  1527. if (!addr)
  1528. return EINVAL;
  1529. switch (type) {
  1530. case AF_INET:
  1531. if (len != sizeof(struct in_addr))
  1532. return EINVAL;
  1533. break;
  1534. #ifdef __UCLIBC_HAS_IPV6__
  1535. case AF_INET6:
  1536. if (len != sizeof(struct in6_addr))
  1537. return EINVAL;
  1538. break;
  1539. #endif /* __UCLIBC_HAS_IPV6__ */
  1540. default:
  1541. return EINVAL;
  1542. }
  1543. /* do /etc/hosts first */
  1544. if ((i=get_hosts_byaddr_r(addr, len, type, result_buf,
  1545. buf, buflen, result, h_errnop))==0)
  1546. return i;
  1547. switch (*h_errnop) {
  1548. case HOST_NOT_FOUND:
  1549. case NO_ADDRESS:
  1550. break;
  1551. default:
  1552. return i;
  1553. }
  1554. open_nameservers();
  1555. #ifdef __UCLIBC_HAS_IPV6__
  1556. qp=buf;
  1557. plen=buflen;
  1558. #endif /* __UCLIBC_HAS_IPV6__ */
  1559. *h_errnop = NETDB_INTERNAL;
  1560. if (buflen < sizeof(*in))
  1561. return ERANGE;
  1562. in=(struct in_addr*)buf;
  1563. buf+=sizeof(*in);
  1564. buflen-=sizeof(*in);
  1565. if (buflen < sizeof(*addr_list)*2)
  1566. return ERANGE;
  1567. addr_list=(struct in_addr**)buf;
  1568. buf+=sizeof(*addr_list)*2;
  1569. buflen-=sizeof(*addr_list)*2;
  1570. #ifdef __UCLIBC_HAS_IPV6__
  1571. if (plen < sizeof(*in6))
  1572. return ERANGE;
  1573. in6=(struct in6_addr*)qp;
  1574. qp+=sizeof(*in6);
  1575. plen-=sizeof(*in6);
  1576. if (plen < sizeof(*addr_list6)*2)
  1577. return ERANGE;
  1578. addr_list6=(struct in6_addr**)qp;
  1579. qp+=sizeof(*addr_list6)*2;
  1580. plen-=sizeof(*addr_list6)*2;
  1581. if (len < buflen) {
  1582. buflen=len;
  1583. buf=qp;
  1584. }
  1585. #endif /* __UCLIBC_HAS_IPV6__ */
  1586. if (buflen<256)
  1587. return ERANGE;
  1588. if(type == AF_INET) {
  1589. unsigned char *tmp_addr = (unsigned char *)addr;
  1590. memcpy(&in->s_addr, addr, len);
  1591. addr_list[0] = in;
  1592. sprintf(buf, "%u.%u.%u.%u.in-addr.arpa",
  1593. tmp_addr[3], tmp_addr[2], tmp_addr[1], tmp_addr[0]);
  1594. #ifdef __UCLIBC_HAS_IPV6__
  1595. } else {
  1596. memcpy(in6->s6_addr, addr, len);
  1597. addr_list6[0] = in6;
  1598. qp = buf;
  1599. for (i = len - 1; i >= 0; i--) {
  1600. qp += sprintf(qp, "%x.%x.", in6->s6_addr[i] & 0xf,
  1601. (in6->s6_addr[i] >> 4) & 0xf);
  1602. }
  1603. strcpy(qp, "ip6.int");
  1604. #endif /* __UCLIBC_HAS_IPV6__ */
  1605. }
  1606. addr_list[1] = 0;
  1607. for (;;) {
  1608. i = dns_lookup(buf, T_PTR, nameservers, nameserver, &packet, &a);
  1609. if (i < 0) {
  1610. *h_errnop = HOST_NOT_FOUND;
  1611. return TRY_AGAIN;
  1612. }
  1613. strncpy(buf, a.dotted, buflen);
  1614. free(a.dotted);
  1615. if (a.atype == T_CNAME) { /* CNAME */
  1616. DPRINTF("Got a CNAME in gethostbyaddr()\n");
  1617. i = decode_dotted(packet, a.rdoffset, buf, buflen);
  1618. free(packet);
  1619. if (i < 0) {
  1620. *h_errnop = NO_RECOVERY;
  1621. return -1;
  1622. }
  1623. if (++nest > MAX_RECURSE) {
  1624. *h_errnop = NO_RECOVERY;
  1625. return -1;
  1626. }
  1627. continue;
  1628. } else if (a.atype == T_PTR) { /* ADDRESS */
  1629. i = decode_dotted(packet, a.rdoffset, buf, buflen);
  1630. free(packet);
  1631. result_buf->h_name = buf;
  1632. result_buf->h_addrtype = type;
  1633. if(type == AF_INET) {
  1634. result_buf->h_length = sizeof(*in);
  1635. #ifdef __UCLIBC_HAS_IPV6__
  1636. } else {
  1637. result_buf->h_length = sizeof(*in6);
  1638. #endif /* __UCLIBC_HAS_IPV6__ */
  1639. }
  1640. result_buf->h_addr_list = (char **) addr_list;
  1641. break;
  1642. } else {
  1643. free(packet);
  1644. *h_errnop = NO_ADDRESS;
  1645. return TRY_AGAIN;
  1646. }
  1647. }
  1648. *result=result_buf;
  1649. return NETDB_SUCCESS;
  1650. }
  1651. #endif