1 /* $NetBSD: getnameinfo.c,v 1.60 2023/09/08 18:17:41 christos Exp $ */ 2 /* $KAME: getnameinfo.c,v 1.45 2000/09/25 22:43:56 itojun Exp $ */ 3 4 /* 5 * Copyright (c) 2000 Ben Harris. 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Issues to be discussed: 36 * - Thread safe-ness must be checked 37 * - RFC2553 says that we should raise error on short buffer. X/Open says 38 * we need to truncate the result. We obey RFC2553 (and X/Open should be 39 * modified). ipngwg rough consensus seems to follow RFC2553. 40 * - What is "local" in NI_FQDN? 41 * - NI_NAMEREQD and NI_NUMERICHOST conflict with each other. 42 * - (KAME extension) always attach textual scopeid (fe80::1%lo0), if 43 * sin6_scope_id is filled - standardization status? 44 * XXX breaks backward compat for code that expects no scopeid. 45 * beware on merge. 46 */ 47 48 #include <sys/cdefs.h> 49 #if defined(LIBC_SCCS) && !defined(lint) 50 __RCSID("$NetBSD: getnameinfo.c,v 1.60 2023/09/08 18:17:41 christos Exp $"); 51 #endif /* LIBC_SCCS and not lint */ 52 53 #ifndef RUMP_ACTION 54 #include "namespace.h" 55 #endif 56 #include <sys/types.h> 57 #include <sys/socket.h> 58 #include <sys/un.h> 59 #include <net/if.h> 60 #include <net/if_dl.h> 61 #include <net/if_ieee1394.h> 62 #include <net/if_types.h> 63 #include <netatalk/at.h> 64 #include <netinet/in.h> 65 #include <arpa/inet.h> 66 #include <arpa/nameser.h> 67 #include <assert.h> 68 #include <limits.h> 69 #include <netdb.h> 70 #include <resolv.h> 71 #include <stddef.h> 72 #include <string.h> 73 74 #include "servent.h" 75 #include "hostent.h" 76 77 #ifndef RUMP_ACTION 78 #ifdef __weak_alias 79 __weak_alias(getnameinfo,_getnameinfo) 80 #endif 81 #endif 82 83 static const struct afd { 84 int a_af; 85 socklen_t a_addrlen; 86 socklen_t a_socklen; 87 int a_off; 88 } afdl [] = { 89 #ifdef INET6 90 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), 91 offsetof(struct sockaddr_in6, sin6_addr)}, 92 #endif 93 {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), 94 offsetof(struct sockaddr_in, sin_addr)}, 95 {0, 0, 0, 0}, 96 }; 97 98 struct sockinet { 99 u_char si_len; 100 u_char si_family; 101 u_short si_port; 102 }; 103 104 static int getnameinfo_inet(const struct sockaddr *, socklen_t, char *, 105 socklen_t, char *, socklen_t, int); 106 #ifdef INET6 107 static int ip6_parsenumeric(const struct sockaddr *, const char *, char *, 108 socklen_t, int); 109 static int ip6_sa2str(const struct sockaddr_in6 *, char *, size_t, int); 110 #endif 111 static int getnameinfo_atalk(const struct sockaddr *, socklen_t, char *, 112 socklen_t, char *, socklen_t, int); 113 static int getnameinfo_local(const struct sockaddr *, socklen_t, char *, 114 socklen_t, char *, socklen_t, int); 115 116 static int getnameinfo_link(const struct sockaddr *, socklen_t, char *, 117 socklen_t, char *, socklen_t, int); 118 static int hexname(const uint8_t *, size_t, char *, socklen_t); 119 120 /* 121 * Top-level getnameinfo() code. Look at the address family, and pick an 122 * appropriate function to call. 123 */ 124 int 125 getnameinfo(const struct sockaddr *sa, socklen_t salen, 126 char *host, socklen_t hostlen, 127 char *serv, socklen_t servlen, 128 int flags) 129 { 130 131 /* 132 * getnameinfo() accepts an salen of sizeof(struct sockaddr_storage) 133 * at maximum as shown in RFC 4038 Sec.6.2.3. 134 */ 135 if (salen > sizeof(struct sockaddr_storage)) 136 return EAI_FAMILY; 137 138 switch (sa->sa_family) { 139 case AF_APPLETALK: 140 return getnameinfo_atalk(sa, salen, host, hostlen, 141 serv, servlen, flags); 142 case AF_INET: 143 case AF_INET6: 144 return getnameinfo_inet(sa, salen, host, hostlen, 145 serv, servlen, flags); 146 case AF_LINK: 147 return getnameinfo_link(sa, salen, host, hostlen, 148 serv, servlen, flags); 149 case AF_LOCAL: 150 return getnameinfo_local(sa, salen, host, hostlen, 151 serv, servlen, flags); 152 default: 153 return EAI_FAMILY; 154 } 155 } 156 157 /* 158 * getnameinfo_atalk(): 159 * Format an AppleTalk address into a printable format. 160 */ 161 /* ARGSUSED */ 162 static int 163 getnameinfo_atalk(const struct sockaddr *sa, socklen_t salen, 164 char *host, socklen_t hostlen, char *serv, socklen_t servlen, 165 int flags) 166 { 167 char numserv[8]; 168 int n, m=0; 169 170 const struct sockaddr_at *sat = 171 (const struct sockaddr_at *)(const void *)sa; 172 173 if (serv != NULL && servlen > 0) { 174 snprintf(numserv, sizeof(numserv), "%u", sat->sat_port); 175 if (strlen(numserv) + 1 > servlen) 176 return EAI_MEMORY; 177 strlcpy(serv, numserv, servlen); 178 } 179 180 n = snprintf(host, hostlen, "%u.%u", 181 ntohs(sat->sat_addr.s_net), sat->sat_addr.s_node); 182 183 if (n < 0 || (socklen_t)(m+n) >= hostlen) 184 goto errout; 185 186 m += n; 187 188 if (sat->sat_range.r_netrange.nr_phase) { 189 n = snprintf(host+m, hostlen-m, " phase %u", 190 sat->sat_range.r_netrange.nr_phase); 191 192 if (n < 0 || (socklen_t)(m+n) >= hostlen) 193 goto errout; 194 195 m += n; 196 } 197 if (sat->sat_range.r_netrange.nr_firstnet) { 198 n = snprintf(host+m, hostlen-m, " range %u - %u", 199 ntohs(sat->sat_range.r_netrange.nr_firstnet), 200 ntohs(sat->sat_range.r_netrange.nr_lastnet )); 201 202 if (n < 0 || (socklen_t)(m+n) >= hostlen) 203 goto errout; 204 205 m += n; 206 } 207 208 return 0; 209 210 errout: 211 if (host && hostlen>0) 212 host[m] = '\0'; /* XXX ??? */ 213 214 return EAI_MEMORY; 215 } 216 217 /* 218 * getnameinfo_local(): 219 * Format an local address into a printable format. 220 */ 221 /* ARGSUSED */ 222 static int 223 getnameinfo_local(const struct sockaddr *sa, socklen_t salen, 224 char *host, socklen_t hostlen, char *serv, socklen_t servlen, 225 int flags) 226 { 227 const struct sockaddr_un *sun = 228 (const struct sockaddr_un *)(const void *)sa; 229 230 if (salen <= sizeof(*sun) - sizeof(sun->sun_path)) 231 return EAI_FAMILY; 232 233 if (serv != NULL && servlen > 0) 234 serv[0] = '\0'; 235 236 if (host && hostlen > 0) 237 strlcpy(host, sun->sun_path, 238 MIN(sizeof(sun->sun_path) + 1, hostlen)); 239 240 return 0; 241 } 242 243 /* 244 * getnameinfo_inet(): 245 * Format an IPv4 or IPv6 sockaddr into a printable string. 246 */ 247 static int 248 getnameinfo_inet(const struct sockaddr *sa, socklen_t salen, 249 char *host, socklen_t hostlen, 250 char *serv, socklen_t servlen, 251 int flags) 252 { 253 const struct afd *afd; 254 struct servent *sp; 255 struct hostent *hp; 256 u_short port; 257 int family, i; 258 const char *addr; 259 uint32_t v4a; 260 char numserv[512]; 261 char numaddr[512]; 262 263 /* sa is checked below */ 264 /* host may be NULL */ 265 /* serv may be NULL */ 266 267 if (sa == NULL) 268 return EAI_FAIL; 269 270 family = sa->sa_family; 271 for (i = 0; afdl[i].a_af; i++) 272 if (afdl[i].a_af == family) { 273 afd = &afdl[i]; 274 goto found; 275 } 276 return EAI_FAMILY; 277 278 found: 279 if (salen < afd->a_socklen) 280 return EAI_FAMILY; 281 282 /* network byte order */ 283 port = ((const struct sockinet *)(const void *)sa)->si_port; 284 addr = (const char *)(const void *)sa + afd->a_off; 285 286 if (serv == NULL || servlen == 0) { 287 /* 288 * do nothing in this case. 289 * in case you are wondering if "&&" is more correct than 290 * "||" here: rfc2553bis-03 says that serv == NULL OR 291 * servlen == 0 means that the caller does not want the result. 292 */ 293 } else { 294 struct servent_data svd; 295 struct servent sv; 296 297 if (flags & NI_NUMERICSERV) 298 sp = NULL; 299 else { 300 (void)memset(&svd, 0, sizeof(svd)); 301 sp = getservbyport_r(port, 302 (flags & NI_DGRAM) ? "udp" : "tcp", &sv, &svd); 303 } 304 if (sp) { 305 if (strlen(sp->s_name) + 1 > servlen) { 306 endservent_r(&svd); 307 return EAI_MEMORY; 308 } 309 strlcpy(serv, sp->s_name, servlen); 310 endservent_r(&svd); 311 } else { 312 snprintf(numserv, sizeof(numserv), "%u", ntohs(port)); 313 if (strlen(numserv) + 1 > servlen) 314 return EAI_MEMORY; 315 strlcpy(serv, numserv, servlen); 316 } 317 } 318 319 switch (sa->sa_family) { 320 case AF_INET: 321 v4a = (uint32_t) 322 ntohl(((const struct sockaddr_in *) 323 (const void *)sa)->sin_addr.s_addr); 324 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) 325 flags |= NI_NUMERICHOST; 326 v4a >>= IN_CLASSA_NSHIFT; 327 if (v4a == 0) 328 flags |= NI_NUMERICHOST; 329 break; 330 #ifdef INET6 331 case AF_INET6: 332 { 333 const struct sockaddr_in6 *sin6; 334 sin6 = (const struct sockaddr_in6 *)(const void *)sa; 335 switch (sin6->sin6_addr.s6_addr[0]) { 336 case 0x00: 337 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) 338 ; 339 else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 340 ; 341 else 342 flags |= NI_NUMERICHOST; 343 break; 344 default: 345 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) { 346 flags |= NI_NUMERICHOST; 347 } 348 else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 349 flags |= NI_NUMERICHOST; 350 break; 351 } 352 } 353 break; 354 #endif 355 } 356 if (host == NULL || hostlen == 0) { 357 /* 358 * do nothing in this case. 359 * in case you are wondering if "&&" is more correct than 360 * "||" here: rfc2553bis-03 says that host == NULL or 361 * hostlen == 0 means that the caller does not want the result. 362 */ 363 } else if (flags & NI_NUMERICHOST) { 364 size_t numaddrlen; 365 366 /* NUMERICHOST and NAMEREQD conflicts with each other */ 367 if (flags & NI_NAMEREQD) 368 return EAI_NONAME; 369 370 switch(afd->a_af) { 371 #ifdef INET6 372 case AF_INET6: 373 { 374 int error; 375 376 if ((error = ip6_parsenumeric(sa, addr, host, 377 hostlen, flags)) != 0) 378 return(error); 379 break; 380 } 381 #endif 382 default: 383 if (inet_ntop(afd->a_af, addr, numaddr, 384 (socklen_t)sizeof(numaddr)) == NULL) 385 return EAI_SYSTEM; 386 numaddrlen = strlen(numaddr); 387 if (numaddrlen + 1 > hostlen) /* don't forget terminator */ 388 return EAI_MEMORY; 389 strlcpy(host, numaddr, hostlen); 390 break; 391 } 392 } else { 393 struct hostent hent; 394 char hbuf[4096]; 395 int he; 396 hp = gethostbyaddr_r(addr, afd->a_addrlen, afd->a_af, &hent, 397 hbuf, sizeof(hbuf), &he); 398 399 if (hp) { 400 #if 0 401 /* 402 * commented out, since "for local host" is not 403 * implemented here - see RFC2553 p30 404 */ 405 if (flags & NI_NOFQDN) { 406 char *p; 407 p = strchr(hp->h_name, '.'); 408 if (p) 409 *p = '\0'; 410 } 411 #endif 412 if (strlen(hp->h_name) + 1 > hostlen) { 413 return EAI_MEMORY; 414 } 415 strlcpy(host, hp->h_name, hostlen); 416 } else { 417 switch (he) { 418 case NO_DATA: 419 case HOST_NOT_FOUND: 420 if (flags & NI_NAMEREQD) 421 return EAI_NONAME; 422 break; 423 case TRY_AGAIN: 424 return EAI_AGAIN; 425 case NETDB_SUCCESS: 426 case NETDB_INTERNAL: 427 case NO_RECOVERY: 428 /*FALLTHROUGH*/ 429 default: 430 return EAI_SYSTEM; 431 } 432 switch(afd->a_af) { 433 #ifdef INET6 434 case AF_INET6: 435 { 436 int error; 437 438 if ((error = ip6_parsenumeric(sa, addr, host, 439 hostlen, 440 flags)) != 0) 441 return(error); 442 break; 443 } 444 #endif 445 default: 446 if (inet_ntop(afd->a_af, addr, host, 447 hostlen) == NULL) 448 return EAI_SYSTEM; 449 break; 450 } 451 } 452 } 453 return(0); 454 } 455 456 #ifdef INET6 457 static int 458 ip6_parsenumeric(const struct sockaddr *sa, const char *addr, char *host, 459 socklen_t hostlen, int flags) 460 { 461 size_t numaddrlen; 462 char numaddr[512]; 463 464 _DIAGASSERT(sa != NULL); 465 _DIAGASSERT(addr != NULL); 466 _DIAGASSERT(host != NULL); 467 468 if (inet_ntop(AF_INET6, addr, numaddr, (socklen_t)sizeof(numaddr)) 469 == NULL) 470 return EAI_SYSTEM; 471 472 numaddrlen = strlen(numaddr); 473 if (numaddrlen + 1 > hostlen) /* don't forget terminator */ 474 return EAI_OVERFLOW; 475 strlcpy(host, numaddr, hostlen); 476 477 if (((const struct sockaddr_in6 *)(const void *)sa)->sin6_scope_id) { 478 char zonebuf[MAXHOSTNAMELEN]; 479 int zonelen; 480 481 zonelen = ip6_sa2str( 482 (const struct sockaddr_in6 *)(const void *)sa, 483 zonebuf, sizeof(zonebuf), flags); 484 if (zonelen < 0) 485 return EAI_OVERFLOW; 486 if ((size_t) zonelen + 1 + numaddrlen + 1 > hostlen) 487 return EAI_OVERFLOW; 488 /* construct <numeric-addr><delim><zoneid> */ 489 memcpy(host + numaddrlen + 1, zonebuf, 490 (size_t)zonelen); 491 host[numaddrlen] = SCOPE_DELIMITER; 492 host[numaddrlen + 1 + zonelen] = '\0'; 493 } 494 495 return 0; 496 } 497 498 /* ARGSUSED */ 499 static int 500 ip6_sa2str(const struct sockaddr_in6 *sa6, char *buf, size_t bufsiz, int flags) 501 { 502 unsigned int ifindex; 503 const struct in6_addr *a6; 504 int n; 505 506 _DIAGASSERT(sa6 != NULL); 507 _DIAGASSERT(buf != NULL); 508 509 ifindex = (unsigned int)sa6->sin6_scope_id; 510 a6 = &sa6->sin6_addr; 511 512 #ifdef NI_NUMERICSCOPE 513 if ((flags & NI_NUMERICSCOPE) != 0) { 514 n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id); 515 if (n < 0 || (size_t)n >= bufsiz) 516 return -1; 517 else 518 return n; 519 } 520 #endif 521 522 /* if_indextoname() does not take buffer size. not a good api... */ 523 if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) && 524 bufsiz >= IF_NAMESIZE) { 525 char *p = if_indextoname(ifindex, buf); 526 if (p) { 527 return (int)strlen(p); 528 } 529 } 530 531 /* last resort */ 532 n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id); 533 if (n < 0 || (size_t) n >= bufsiz) 534 return -1; 535 else 536 return n; 537 } 538 #endif /* INET6 */ 539 540 541 /* 542 * getnameinfo_link(): 543 * Format a link-layer address into a printable format, paying attention to 544 * the interface type. 545 */ 546 /* ARGSUSED */ 547 static int 548 getnameinfo_link(const struct sockaddr *sa, socklen_t salen, 549 char *host, socklen_t hostlen, char *serv, socklen_t servlen, 550 int flags) 551 { 552 const struct sockaddr_dl *sdl = 553 (const struct sockaddr_dl *)(const void *)sa; 554 const struct ieee1394_hwaddr *iha; 555 int n; 556 557 if (salen <= sizeof(*sdl) - sizeof(sdl->sdl_data)) 558 return EAI_FAMILY; 559 560 if (serv != NULL && servlen > 0) 561 *serv = '\0'; 562 563 if (sdl->sdl_nlen == 0 && sdl->sdl_alen == 0 && sdl->sdl_slen == 0) { 564 n = snprintf(host, hostlen, "link#%u", sdl->sdl_index); 565 goto out; 566 } 567 568 switch (sdl->sdl_type) { 569 #ifdef IFT_ECONET 570 case IFT_ECONET: 571 if (sdl->sdl_alen < 2) 572 return EAI_FAMILY; 573 if (CLLADDR(sdl)[1] == 0) 574 n = snprintf(host, hostlen, "%u", CLLADDR(sdl)[0]); 575 else 576 n = snprintf(host, hostlen, "%u.%u", 577 CLLADDR(sdl)[1], CLLADDR(sdl)[0]); 578 goto out; 579 #endif 580 case IFT_IEEE1394: 581 if (sdl->sdl_alen < sizeof(iha->iha_uid)) 582 return EAI_FAMILY; 583 iha = 584 (const struct ieee1394_hwaddr *)(const void *)CLLADDR(sdl); 585 return hexname(iha->iha_uid, sizeof(iha->iha_uid), 586 host, hostlen); 587 /* 588 * The following have zero-length addresses. 589 * IFT_ATM (net/if_atmsubr.c) 590 * IFT_FAITH (net/if_faith.c) 591 * IFT_GIF (net/if_gif.c) 592 * IFT_LOOP (net/if_loop.c) 593 * IFT_PPP (net/if_ppp.c, net/if_spppsubr.c) 594 * IFT_SLIP (net/if_sl.c, net/if_strip.c) 595 * IFT_STF (net/if_stf.c) 596 * IFT_L2VLAN (net/if_vlan.c) 597 * IFT_PROPVIRTUAL (net/if_bridge.h> 598 */ 599 /* 600 * The following use IPv4 addresses as link-layer addresses: 601 * IFT_OTHER (net/if_gre.c) 602 */ 603 case IFT_ARCNET: /* default below is believed correct for all these. */ 604 case IFT_ETHER: 605 case IFT_FDDI: 606 case IFT_HIPPI: 607 case IFT_ISO88025: 608 default: 609 return hexname((const uint8_t *)CLLADDR(sdl), 610 (size_t)sdl->sdl_alen, host, hostlen); 611 } 612 out: 613 if (n < 0 || (socklen_t) n >= hostlen) { 614 *host = '\0'; 615 return EAI_MEMORY; 616 } 617 return 0; 618 } 619 620 static int 621 hexname(const uint8_t *cp, size_t len, char *host, socklen_t hostlen) 622 { 623 int n; 624 size_t i; 625 char *outp = host; 626 627 *outp = '\0'; 628 for (i = 0; i < len; i++) { 629 n = snprintf(outp, hostlen, "%s%02x", 630 i ? ":" : "", cp[i]); 631 if (n < 0 || (socklen_t) n >= hostlen) { 632 *host = '\0'; 633 return EAI_MEMORY; 634 } 635 outp += n; 636 hostlen -= n; 637 } 638 return 0; 639 } 640
Indexes created Sat Sep 27 22:09:54 GMT 2025