lib/libc/net/gethnamaddr.c
C | 1441 lines | 1213 code | 121 blank | 107 comment | 350 complexity | d8c5975f791401d11a61a7b079b86d8f MD5 | raw file
Possible License(s): MIT, WTFPL, AGPL-1.0, BSD-3-Clause, GPL-3.0, LGPL-2.0, JSON, 0BSD
- /* $NetBSD: gethnamaddr.c,v 1.76 2010/08/29 15:40:35 christos Exp $ */
- /*
- * ++Copyright++ 1985, 1988, 1993
- * -
- * Copyright (c) 1985, 1988, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * -
- * Portions Copyright (c) 1993 by Digital Equipment Corporation.
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies, and that
- * the name of Digital Equipment Corporation not be used in advertising or
- * publicity pertaining to distribution of the document or software without
- * specific, written prior permission.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
- * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
- * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
- * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
- * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
- * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
- * SOFTWARE.
- * -
- * --Copyright--
- */
- #include <sys/cdefs.h>
- #if defined(LIBC_SCCS) && !defined(lint)
- #if 0
- static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93";
- static char rcsid[] = "Id: gethnamaddr.c,v 8.21 1997/06/01 20:34:37 vixie Exp ";
- #else
- __RCSID("$NetBSD: gethnamaddr.c,v 1.76 2010/08/29 15:40:35 christos Exp $");
- #endif
- #endif /* LIBC_SCCS and not lint */
- #if defined(_LIBC)
- #include "namespace.h"
- #endif
- #include <sys/param.h>
- #include <sys/socket.h>
- #include <netinet/in.h>
- #include <arpa/inet.h>
- #include <arpa/nameser.h>
- #include <assert.h>
- #include <ctype.h>
- #include <errno.h>
- #include <netdb.h>
- #include <resolv.h>
- #include <stdarg.h>
- #include <stdio.h>
- #include <syslog.h>
- #ifndef LOG_AUTH
- # define LOG_AUTH 0
- #endif
- #define MULTI_PTRS_ARE_ALIASES 1 /* XXX - experimental */
- #include <nsswitch.h>
- #include <stdlib.h>
- #include <string.h>
- #ifdef YP
- #include <rpc/rpc.h>
- #include <rpcsvc/yp_prot.h>
- #include <rpcsvc/ypclnt.h>
- #endif
- #if defined(_LIBC) && defined(__weak_alias)
- __weak_alias(gethostbyaddr,_gethostbyaddr)
- __weak_alias(gethostbyname,_gethostbyname)
- __weak_alias(gethostent,_gethostent)
- #endif
- #define MAXALIASES 35
- #define MAXADDRS 35
- static const char AskedForGot[] =
- "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
- static char *h_addr_ptrs[MAXADDRS + 1];
- #ifdef YP
- static char *__ypdomain;
- #endif
- static struct hostent host;
- static char *host_aliases[MAXALIASES];
- static char hostbuf[8*1024];
- static u_int32_t host_addr[16 / sizeof(u_int32_t)]; /* IPv4 or IPv6 */
- static FILE *hostf = NULL;
- static int stayopen = 0;
- #define MAXPACKET (64*1024)
- typedef union {
- HEADER hdr;
- u_char buf[MAXPACKET];
- } querybuf;
- typedef union {
- int32_t al;
- char ac;
- } align;
- #ifdef DEBUG
- static void debugprintf(const char *, res_state, ...)
- __attribute__((__format__(__printf__, 1, 3)));
- #endif
- static struct hostent *getanswer(const querybuf *, int, const char *, int,
- res_state);
- static void map_v4v6_address(const char *, char *);
- static void map_v4v6_hostent(struct hostent *, char **, char *);
- static void addrsort(char **, int, res_state);
- void _sethtent(int);
- void _endhtent(void);
- struct hostent *_gethtent(void);
- void ht_sethostent(int);
- void ht_endhostent(void);
- struct hostent *ht_gethostbyname(char *);
- struct hostent *ht_gethostbyaddr(const char *, int, int);
- void dns_service(void);
- #undef dn_skipname
- int dn_skipname(const u_char *, const u_char *);
- int _gethtbyaddr(void *, void *, va_list);
- int _gethtbyname(void *, void *, va_list);
- struct hostent *_gethtbyname2(const char *, int);
- int _dns_gethtbyaddr(void *, void *, va_list);
- int _dns_gethtbyname(void *, void *, va_list);
- #ifdef YP
- struct hostent *_yphostent(char *, int);
- int _yp_gethtbyaddr(void *, void *, va_list);
- int _yp_gethtbyname(void *, void *, va_list);
- #endif
- static struct hostent *gethostbyname_internal(const char *, int, res_state);
- static const ns_src default_dns_files[] = {
- { NSSRC_FILES, NS_SUCCESS },
- { NSSRC_DNS, NS_SUCCESS },
- { 0, 0 }
- };
- #ifdef DEBUG
- static void
- debugprintf(const char *msg, res_state res, ...)
- {
- _DIAGASSERT(msg != NULL);
- if (res->options & RES_DEBUG) {
- int save = errno;
- va_list ap;
- va_start (ap, res);
- vprintf(msg, ap);
- va_end (ap);
-
- errno = save;
- }
- }
- #else
- # define debugprintf(msg, res, num) /*nada*/
- #endif
- #define BOUNDED_INCR(x) \
- do { \
- cp += (x); \
- if (cp > eom) { \
- h_errno = NO_RECOVERY; \
- return NULL; \
- } \
- } while (/*CONSTCOND*/0)
- #define BOUNDS_CHECK(ptr, count) \
- do { \
- if ((ptr) + (count) > eom) { \
- h_errno = NO_RECOVERY; \
- return NULL; \
- } \
- } while (/*CONSTCOND*/0)
- static struct hostent *
- getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
- res_state res)
- {
- const HEADER *hp;
- const u_char *cp;
- int n;
- const u_char *eom, *erdata;
- char *bp, **ap, **hap, *ep;
- int type, class, ancount, qdcount;
- int haveanswer, had_error;
- int toobig = 0;
- char tbuf[MAXDNAME];
- const char *tname;
- int (*name_ok)(const char *);
- _DIAGASSERT(answer != NULL);
- _DIAGASSERT(qname != NULL);
- tname = qname;
- host.h_name = NULL;
- eom = answer->buf + anslen;
- switch (qtype) {
- case T_A:
- case T_AAAA:
- name_ok = res_hnok;
- break;
- case T_PTR:
- name_ok = res_dnok;
- break;
- default:
- return NULL; /* XXX should be abort(); */
- }
- /*
- * find first satisfactory answer
- */
- hp = &answer->hdr;
- ancount = ntohs(hp->ancount);
- qdcount = ntohs(hp->qdcount);
- bp = hostbuf;
- ep = hostbuf + sizeof hostbuf;
- cp = answer->buf;
- BOUNDED_INCR(HFIXEDSZ);
- if (qdcount != 1) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
- if ((n < 0) || !(*name_ok)(bp)) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- BOUNDED_INCR(n + QFIXEDSZ);
- if (qtype == T_A || qtype == T_AAAA) {
- /* res_send() has already verified that the query name is the
- * same as the one we sent; this just gets the expanded name
- * (i.e., with the succeeding search-domain tacked on).
- */
- n = strlen(bp) + 1; /* for the \0 */
- if (n >= MAXHOSTNAMELEN) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- host.h_name = bp;
- bp += n;
- /* The qname can be abbreviated, but h_name is now absolute. */
- qname = host.h_name;
- }
- ap = host_aliases;
- *ap = NULL;
- host.h_aliases = host_aliases;
- hap = h_addr_ptrs;
- *hap = NULL;
- host.h_addr_list = h_addr_ptrs;
- haveanswer = 0;
- had_error = 0;
- while (ancount-- > 0 && cp < eom && !had_error) {
- n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
- if ((n < 0) || !(*name_ok)(bp)) {
- had_error++;
- continue;
- }
- cp += n; /* name */
- BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ);
- type = _getshort(cp);
- cp += INT16SZ; /* type */
- class = _getshort(cp);
- cp += INT16SZ + INT32SZ; /* class, TTL */
- n = _getshort(cp);
- cp += INT16SZ; /* len */
- BOUNDS_CHECK(cp, n);
- erdata = cp + n;
- if (class != C_IN) {
- /* XXX - debug? syslog? */
- cp += n;
- continue; /* XXX - had_error++ ? */
- }
- if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) {
- if (ap >= &host_aliases[MAXALIASES-1])
- continue;
- n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
- if ((n < 0) || !(*name_ok)(tbuf)) {
- had_error++;
- continue;
- }
- cp += n;
- if (cp != erdata) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- /* Store alias. */
- *ap++ = bp;
- n = strlen(bp) + 1; /* for the \0 */
- if (n >= MAXHOSTNAMELEN) {
- had_error++;
- continue;
- }
- bp += n;
- /* Get canonical name. */
- n = strlen(tbuf) + 1; /* for the \0 */
- if (n > ep - bp || n >= MAXHOSTNAMELEN) {
- had_error++;
- continue;
- }
- strlcpy(bp, tbuf, (size_t)(ep - bp));
- host.h_name = bp;
- bp += n;
- continue;
- }
- if (qtype == T_PTR && type == T_CNAME) {
- n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
- if (n < 0 || !res_dnok(tbuf)) {
- had_error++;
- continue;
- }
- cp += n;
- if (cp != erdata) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- /* Get canonical name. */
- n = strlen(tbuf) + 1; /* for the \0 */
- if (n > ep - bp || n >= MAXHOSTNAMELEN) {
- had_error++;
- continue;
- }
- strlcpy(bp, tbuf, (size_t)(ep - bp));
- tname = bp;
- bp += n;
- continue;
- }
- if (type != qtype) {
- if (type != T_KEY && type != T_SIG)
- syslog(LOG_NOTICE|LOG_AUTH,
- "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
- qname, p_class(C_IN), p_type(qtype),
- p_type(type));
- cp += n;
- continue; /* XXX - had_error++ ? */
- }
- switch (type) {
- case T_PTR:
- if (strcasecmp(tname, bp) != 0) {
- syslog(LOG_NOTICE|LOG_AUTH,
- AskedForGot, qname, bp);
- cp += n;
- continue; /* XXX - had_error++ ? */
- }
- n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
- if ((n < 0) || !res_hnok(bp)) {
- had_error++;
- break;
- }
- #if MULTI_PTRS_ARE_ALIASES
- cp += n;
- if (cp != erdata) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- if (!haveanswer)
- host.h_name = bp;
- else if (ap < &host_aliases[MAXALIASES-1])
- *ap++ = bp;
- else
- n = -1;
- if (n != -1) {
- n = strlen(bp) + 1; /* for the \0 */
- if (n >= MAXHOSTNAMELEN) {
- had_error++;
- break;
- }
- bp += n;
- }
- break;
- #else
- host.h_name = bp;
- if (res->options & RES_USE_INET6) {
- n = strlen(bp) + 1; /* for the \0 */
- if (n >= MAXHOSTNAMELEN) {
- had_error++;
- break;
- }
- bp += n;
- map_v4v6_hostent(&host, &bp, ep);
- }
- h_errno = NETDB_SUCCESS;
- return &host;
- #endif
- case T_A:
- case T_AAAA:
- if (strcasecmp(host.h_name, bp) != 0) {
- syslog(LOG_NOTICE|LOG_AUTH,
- AskedForGot, host.h_name, bp);
- cp += n;
- continue; /* XXX - had_error++ ? */
- }
- if (n != host.h_length) {
- cp += n;
- continue;
- }
- if (type == T_AAAA) {
- struct in6_addr in6;
- memcpy(&in6, cp, IN6ADDRSZ);
- if (IN6_IS_ADDR_V4MAPPED(&in6)) {
- cp += n;
- continue;
- }
- }
- if (!haveanswer) {
- int nn;
- host.h_name = bp;
- nn = strlen(bp) + 1; /* for the \0 */
- bp += nn;
- }
- bp += sizeof(align) -
- (size_t)((u_long)bp % sizeof(align));
- if (bp + n >= &hostbuf[sizeof hostbuf]) {
- debugprintf("size (%d) too big\n", res, n);
- had_error++;
- continue;
- }
- if (hap >= &h_addr_ptrs[MAXADDRS-1]) {
- if (!toobig++) {
- debugprintf("Too many addresses (%d)\n",
- res, MAXADDRS);
- }
- cp += n;
- continue;
- }
- (void)memcpy(*hap++ = bp, cp, (size_t)n);
- bp += n;
- cp += n;
- if (cp != erdata) {
- h_errno = NO_RECOVERY;
- return NULL;
- }
- break;
- default:
- abort();
- }
- if (!had_error)
- haveanswer++;
- }
- if (haveanswer) {
- *ap = NULL;
- *hap = NULL;
- /*
- * Note: we sort even if host can take only one address
- * in its return structures - should give it the "best"
- * address in that case, not some random one
- */
- if (res->nsort && haveanswer > 1 && qtype == T_A)
- addrsort(h_addr_ptrs, haveanswer, res);
- if (!host.h_name) {
- n = strlen(qname) + 1; /* for the \0 */
- if (n > ep - bp || n >= MAXHOSTNAMELEN)
- goto no_recovery;
- strlcpy(bp, qname, (size_t)(ep - bp));
- host.h_name = bp;
- bp += n;
- }
- if (res->options & RES_USE_INET6)
- map_v4v6_hostent(&host, &bp, ep);
- h_errno = NETDB_SUCCESS;
- return &host;
- }
- no_recovery:
- h_errno = NO_RECOVERY;
- return NULL;
- }
- struct hostent *
- gethostbyname(const char *name)
- {
- struct hostent *hp;
- res_state res = __res_get_state();
- if (res == NULL)
- return NULL;
- _DIAGASSERT(name != NULL);
- if (res->options & RES_USE_INET6) {
- hp = gethostbyname_internal(name, AF_INET6, res);
- if (hp) {
- __res_put_state(res);
- return hp;
- }
- }
- hp = gethostbyname_internal(name, AF_INET, res);
- __res_put_state(res);
- return hp;
- }
- struct hostent *
- gethostbyname2(const char *name, int af)
- {
- struct hostent *hp;
- res_state res = __res_get_state();
- if (res == NULL)
- return NULL;
- hp = gethostbyname_internal(name, af, res);
- __res_put_state(res);
- return hp;
- }
- static struct hostent *
- gethostbyname_internal(const char *name, int af, res_state res)
- {
- const char *cp;
- char *bp, *ep;
- int size;
- struct hostent *hp;
- static const ns_dtab dtab[] = {
- NS_FILES_CB(_gethtbyname, NULL)
- { NSSRC_DNS, _dns_gethtbyname, NULL }, /* force -DHESIOD */
- NS_NIS_CB(_yp_gethtbyname, NULL)
- NS_NULL_CB
- };
- _DIAGASSERT(name != NULL);
- switch (af) {
- case AF_INET:
- size = INADDRSZ;
- break;
- case AF_INET6:
- size = IN6ADDRSZ;
- break;
- default:
- h_errno = NETDB_INTERNAL;
- errno = EAFNOSUPPORT;
- return NULL;
- }
- host.h_addrtype = af;
- host.h_length = size;
- /*
- * if there aren't any dots, it could be a user-level alias.
- * this is also done in res_nquery() since we are not the only
- * function that looks up host names.
- */
- if (!strchr(name, '.') && (cp = __hostalias(name)))
- name = cp;
- /*
- * disallow names consisting only of digits/dots, unless
- * they end in a dot.
- */
- if (isdigit((u_char) name[0]))
- for (cp = name;; ++cp) {
- if (!*cp) {
- if (*--cp == '.')
- break;
- /*
- * All-numeric, no dot at the end.
- * Fake up a hostent as if we'd actually
- * done a lookup.
- */
- if (inet_pton(af, name,
- (char *)(void *)host_addr) <= 0) {
- h_errno = HOST_NOT_FOUND;
- return NULL;
- }
- strncpy(hostbuf, name, MAXDNAME);
- hostbuf[MAXDNAME] = '\0';
- bp = hostbuf + MAXDNAME;
- ep = hostbuf + sizeof hostbuf;
- host.h_name = hostbuf;
- host.h_aliases = host_aliases;
- host_aliases[0] = NULL;
- h_addr_ptrs[0] = (char *)(void *)host_addr;
- h_addr_ptrs[1] = NULL;
- host.h_addr_list = h_addr_ptrs;
- if (res->options & RES_USE_INET6)
- map_v4v6_hostent(&host, &bp, ep);
- h_errno = NETDB_SUCCESS;
- return &host;
- }
- if (!isdigit((u_char) *cp) && *cp != '.')
- break;
- }
- if ((isxdigit((u_char) name[0]) && strchr(name, ':') != NULL) ||
- name[0] == ':')
- for (cp = name;; ++cp) {
- if (!*cp) {
- if (*--cp == '.')
- break;
- /*
- * All-IPv6-legal, no dot at the end.
- * Fake up a hostent as if we'd actually
- * done a lookup.
- */
- if (inet_pton(af, name,
- (char *)(void *)host_addr) <= 0) {
- h_errno = HOST_NOT_FOUND;
- return NULL;
- }
- strncpy(hostbuf, name, MAXDNAME);
- hostbuf[MAXDNAME] = '\0';
- bp = hostbuf + MAXDNAME;
- ep = hostbuf + sizeof hostbuf;
- host.h_name = hostbuf;
- host.h_aliases = host_aliases;
- host_aliases[0] = NULL;
- h_addr_ptrs[0] = (char *)(void *)host_addr;
- h_addr_ptrs[1] = NULL;
- host.h_addr_list = h_addr_ptrs;
- h_errno = NETDB_SUCCESS;
- return &host;
- }
- if (!isxdigit((u_char) *cp) && *cp != ':' && *cp != '.')
- break;
- }
- hp = NULL;
- h_errno = NETDB_INTERNAL;
- if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyname",
- default_dns_files, name, strlen(name), af) != NS_SUCCESS)
- return NULL;
- h_errno = NETDB_SUCCESS;
- return hp;
- }
- struct hostent *
- gethostbyaddr(const char *addr, /* XXX should have been def'd as u_char! */
- socklen_t len, int af)
- {
- const u_char *uaddr = (const u_char *)addr;
- socklen_t size;
- struct hostent *hp;
- static const ns_dtab dtab[] = {
- NS_FILES_CB(_gethtbyaddr, NULL)
- { NSSRC_DNS, _dns_gethtbyaddr, NULL }, /* force -DHESIOD */
- NS_NIS_CB(_yp_gethtbyaddr, NULL)
- NS_NULL_CB
- };
-
- _DIAGASSERT(addr != NULL);
- if (af == AF_INET6 && len == IN6ADDRSZ &&
- (IN6_IS_ADDR_LINKLOCAL((const struct in6_addr *)(const void *)uaddr) ||
- IN6_IS_ADDR_SITELOCAL((const struct in6_addr *)(const void *)uaddr))) {
- h_errno = HOST_NOT_FOUND;
- return NULL;
- }
- if (af == AF_INET6 && len == IN6ADDRSZ &&
- (IN6_IS_ADDR_V4MAPPED((const struct in6_addr *)(const void *)uaddr) ||
- IN6_IS_ADDR_V4COMPAT((const struct in6_addr *)(const void *)uaddr))) {
- /* Unmap. */
- addr += IN6ADDRSZ - INADDRSZ;
- uaddr += IN6ADDRSZ - INADDRSZ;
- af = AF_INET;
- len = INADDRSZ;
- }
- switch (af) {
- case AF_INET:
- size = INADDRSZ;
- break;
- case AF_INET6:
- size = IN6ADDRSZ;
- break;
- default:
- errno = EAFNOSUPPORT;
- h_errno = NETDB_INTERNAL;
- return NULL;
- }
- if (size != len) {
- errno = EINVAL;
- h_errno = NETDB_INTERNAL;
- return NULL;
- }
- hp = NULL;
- h_errno = NETDB_INTERNAL;
- if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyaddr",
- default_dns_files, uaddr, len, af) != NS_SUCCESS)
- return NULL;
- h_errno = NETDB_SUCCESS;
- return hp;
- }
- void
- _sethtent(int f)
- {
- if (!hostf)
- hostf = fopen(_PATH_HOSTS, "r" );
- else
- rewind(hostf);
- stayopen = f;
- }
- void
- _endhtent(void)
- {
- if (hostf && !stayopen) {
- (void) fclose(hostf);
- hostf = NULL;
- }
- }
- struct hostent *
- _gethtent(void)
- {
- char *p;
- char *cp, **q;
- int af, len;
- if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) {
- h_errno = NETDB_INTERNAL;
- return NULL;
- }
- again:
- if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) {
- h_errno = HOST_NOT_FOUND;
- return NULL;
- }
- if (*p == '#')
- goto again;
- if (!(cp = strpbrk(p, "#\n")))
- goto again;
- *cp = '\0';
- if (!(cp = strpbrk(p, " \t")))
- goto again;
- *cp++ = '\0';
- if (inet_pton(AF_INET6, p, (char *)(void *)host_addr) > 0) {
- af = AF_INET6;
- len = IN6ADDRSZ;
- } else if (inet_pton(AF_INET, p, (char *)(void *)host_addr) > 0) {
- res_state res = __res_get_state();
- if (res == NULL)
- return NULL;
- if (res->options & RES_USE_INET6) {
- map_v4v6_address((char *)(void *)host_addr,
- (char *)(void *)host_addr);
- af = AF_INET6;
- len = IN6ADDRSZ;
- } else {
- af = AF_INET;
- len = INADDRSZ;
- }
- __res_put_state(res);
- } else {
- goto again;
- }
- /* if this is not something we're looking for, skip it. */
- if (host.h_addrtype != 0 && host.h_addrtype != af)
- goto again;
- if (host.h_length != 0 && host.h_length != len)
- goto again;
- h_addr_ptrs[0] = (char *)(void *)host_addr;
- h_addr_ptrs[1] = NULL;
- host.h_addr_list = h_addr_ptrs;
- host.h_length = len;
- host.h_addrtype = af;
- while (*cp == ' ' || *cp == '\t')
- cp++;
- host.h_name = cp;
- q = host.h_aliases = host_aliases;
- if ((cp = strpbrk(cp, " \t")) != NULL)
- *cp++ = '\0';
- while (cp && *cp) {
- if (*cp == ' ' || *cp == '\t') {
- cp++;
- continue;
- }
- if (q < &host_aliases[MAXALIASES - 1])
- *q++ = cp;
- if ((cp = strpbrk(cp, " \t")) != NULL)
- *cp++ = '\0';
- }
- *q = NULL;
- h_errno = NETDB_SUCCESS;
- return &host;
- }
- /*ARGSUSED*/
- int
- _gethtbyname(void *rv, void *cb_data, va_list ap)
- {
- struct hostent *hp;
- const char *name;
- int af;
- _DIAGASSERT(rv != NULL);
- name = va_arg(ap, char *);
- /* NOSTRICT skip len */(void)va_arg(ap, int);
- af = va_arg(ap, int);
- hp = NULL;
- #if 0
- {
- res_state res = __res_get_state();
- if (res == NULL)
- return NS_NOTFOUND;
- if (res->options & RES_USE_INET6)
- hp = _gethtbyname2(name, AF_INET6);
- if (hp==NULL)
- hp = _gethtbyname2(name, AF_INET);
- __res_put_state(res);
- }
- #else
- hp = _gethtbyname2(name, af);
- #endif
- *((struct hostent **)rv) = hp;
- if (hp == NULL) {
- h_errno = HOST_NOT_FOUND;
- return NS_NOTFOUND;
- }
- return NS_SUCCESS;
- }
- struct hostent *
- _gethtbyname2(const char *name, int af)
- {
- struct hostent *p;
- char *tmpbuf, *ptr, **cp;
- int num;
- size_t len;
- _DIAGASSERT(name != NULL);
- _sethtent(stayopen);
- ptr = tmpbuf = NULL;
- num = 0;
- while ((p = _gethtent()) != NULL && num < MAXADDRS) {
- if (p->h_addrtype != af)
- continue;
- if (strcasecmp(p->h_name, name) != 0) {
- for (cp = p->h_aliases; *cp != NULL; cp++)
- if (strcasecmp(*cp, name) == 0)
- break;
- if (*cp == NULL) continue;
- }
- if (num == 0) {
- size_t bufsize;
- char *src;
- bufsize = strlen(p->h_name) + 2 +
- MAXADDRS * p->h_length +
- ALIGNBYTES;
- for (cp = p->h_aliases; *cp != NULL; cp++)
- bufsize += strlen(*cp) + 1;
- if ((tmpbuf = malloc(bufsize)) == NULL) {
- h_errno = NETDB_INTERNAL;
- return NULL;
- }
- ptr = tmpbuf;
- src = p->h_name;
- while ((*ptr++ = *src++) != '\0');
- for (cp = p->h_aliases; *cp != NULL; cp++) {
- src = *cp;
- while ((*ptr++ = *src++) != '\0');
- }
- *ptr++ = '\0';
- ptr = (char *)(void *)ALIGN(ptr);
- }
- (void)memcpy(ptr, p->h_addr_list[0], (size_t)p->h_length);
- ptr += p->h_length;
- num++;
- }
- _endhtent();
- if (num == 0) return NULL;
- len = ptr - tmpbuf;
- if (len > (sizeof(hostbuf) - ALIGNBYTES)) {
- free(tmpbuf);
- errno = ENOSPC;
- h_errno = NETDB_INTERNAL;
- return NULL;
- }
- ptr = memcpy((void *)ALIGN(hostbuf), tmpbuf, len);
- free(tmpbuf);
- host.h_name = ptr;
- while (*ptr++);
- cp = host_aliases;
- while (*ptr) {
- *cp++ = ptr;
- while (*ptr++);
- }
- ptr++;
- *cp = NULL;
- ptr = (char *)(void *)ALIGN(ptr);
- cp = h_addr_ptrs;
- while (num--) {
- *cp++ = ptr;
- ptr += host.h_length;
- }
- *cp = NULL;
- return &host;
- }
- /*ARGSUSED*/
- int
- _gethtbyaddr(void *rv, void *cb_data, va_list ap)
- {
- struct hostent *p;
- const unsigned char *addr;
- int len, af;
- _DIAGASSERT(rv != NULL);
- addr = va_arg(ap, unsigned char *);
- len = va_arg(ap, int);
- af = va_arg(ap, int);
-
- host.h_length = len;
- host.h_addrtype = af;
- _sethtent(stayopen);
- while ((p = _gethtent()) != NULL)
- if (p->h_addrtype == af && !memcmp(p->h_addr, addr,
- (size_t)len))
- break;
- _endhtent();
- *((struct hostent **)rv) = p;
- if (p==NULL) {
- h_errno = HOST_NOT_FOUND;
- return NS_NOTFOUND;
- }
- return NS_SUCCESS;
- }
- static void
- map_v4v6_address(const char *src, char *dst)
- {
- u_char *p = (u_char *)dst;
- char tmp[INADDRSZ];
- int i;
- _DIAGASSERT(src != NULL);
- _DIAGASSERT(dst != NULL);
- /* Stash a temporary copy so our caller can update in place. */
- (void)memcpy(tmp, src, INADDRSZ);
- /* Mark this ipv6 addr as a mapped ipv4. */
- for (i = 0; i < 10; i++)
- *p++ = 0x00;
- *p++ = 0xff;
- *p++ = 0xff;
- /* Retrieve the saved copy and we're done. */
- (void)memcpy((void *)p, tmp, INADDRSZ);
- }
- static void
- map_v4v6_hostent(struct hostent *hp, char **bpp, char *ep)
- {
- char **ap;
- _DIAGASSERT(hp != NULL);
- _DIAGASSERT(bpp != NULL);
- _DIAGASSERT(ep != NULL);
- if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ)
- return;
- hp->h_addrtype = AF_INET6;
- hp->h_length = IN6ADDRSZ;
- for (ap = hp->h_addr_list; *ap; ap++) {
- int i = sizeof(align) - (size_t)((u_long)*bpp % sizeof(align));
- if (ep - *bpp < (i + IN6ADDRSZ)) {
- /* Out of memory. Truncate address list here. XXX */
- *ap = NULL;
- return;
- }
- *bpp += i;
- map_v4v6_address(*ap, *bpp);
- *ap = *bpp;
- *bpp += IN6ADDRSZ;
- }
- }
- static void
- addrsort(char **ap, int num, res_state res)
- {
- int i, j;
- char **p;
- short aval[MAXADDRS];
- int needsort = 0;
- _DIAGASSERT(ap != NULL);
- p = ap;
- for (i = 0; i < num; i++, p++) {
- for (j = 0 ; (unsigned)j < res->nsort; j++)
- if (res->sort_list[j].addr.s_addr ==
- (((struct in_addr *)(void *)(*p))->s_addr &
- res->sort_list[j].mask))
- break;
- aval[i] = j;
- if (needsort == 0 && i > 0 && j < aval[i-1])
- needsort = i;
- }
- if (!needsort)
- return;
- while (needsort < num) {
- for (j = needsort - 1; j >= 0; j--) {
- if (aval[j] > aval[j+1]) {
- char *hp;
- i = aval[j];
- aval[j] = aval[j+1];
- aval[j+1] = i;
- hp = ap[j];
- ap[j] = ap[j+1];
- ap[j+1] = hp;
- } else
- break;
- }
- needsort++;
- }
- }
- struct hostent *
- gethostent(void)
- {
- host.h_addrtype = 0;
- host.h_length = 0;
- return _gethtent();
- }
- /*ARGSUSED*/
- int
- _dns_gethtbyname(void *rv, void *cb_data, va_list ap)
- {
- querybuf *buf;
- int n, type;
- struct hostent *hp;
- const char *name;
- int af;
- res_state res;
- _DIAGASSERT(rv != NULL);
- name = va_arg(ap, char *);
- /* NOSTRICT skip len */(void)va_arg(ap, int);
- af = va_arg(ap, int);
- switch (af) {
- case AF_INET:
- type = T_A;
- break;
- case AF_INET6:
- type = T_AAAA;
- break;
- default:
- return NS_UNAVAIL;
- }
- buf = malloc(sizeof(*buf));
- if (buf == NULL) {
- h_errno = NETDB_INTERNAL;
- return NS_NOTFOUND;
- }
- res = __res_get_state();
- if (res == NULL) {
- free(buf);
- return NS_NOTFOUND;
- }
- n = res_nsearch(res, name, C_IN, type, buf->buf, sizeof(buf->buf));
- if (n < 0) {
- free(buf);
- debugprintf("res_nsearch failed (%d)\n", res, n);
- __res_put_state(res);
- return NS_NOTFOUND;
- }
- hp = getanswer(buf, n, name, type, res);
- free(buf);
- __res_put_state(res);
- if (hp == NULL)
- switch (h_errno) {
- case HOST_NOT_FOUND:
- return NS_NOTFOUND;
- case TRY_AGAIN:
- return NS_TRYAGAIN;
- default:
- return NS_UNAVAIL;
- }
- *((struct hostent **)rv) = hp;
- return NS_SUCCESS;
- }
- /*ARGSUSED*/
- int
- _dns_gethtbyaddr(void *rv, void *cb_data, va_list ap)
- {
- char qbuf[MAXDNAME + 1], *qp, *ep;
- int n;
- querybuf *buf;
- struct hostent *hp;
- const unsigned char *uaddr;
- int len, af, advance;
- res_state res;
- _DIAGASSERT(rv != NULL);
- uaddr = va_arg(ap, unsigned char *);
- len = va_arg(ap, int);
- af = va_arg(ap, int);
- switch (af) {
- case AF_INET:
- (void)snprintf(qbuf, sizeof(qbuf), "%u.%u.%u.%u.in-addr.arpa",
- (uaddr[3] & 0xff), (uaddr[2] & 0xff),
- (uaddr[1] & 0xff), (uaddr[0] & 0xff));
- break;
- case AF_INET6:
- qp = qbuf;
- ep = qbuf + sizeof(qbuf) - 1;
- for (n = IN6ADDRSZ - 1; n >= 0; n--) {
- advance = snprintf(qp, (size_t)(ep - qp), "%x.%x.",
- uaddr[n] & 0xf,
- ((unsigned int)uaddr[n] >> 4) & 0xf);
- if (advance > 0 && qp + advance < ep)
- qp += advance;
- else {
- h_errno = NETDB_INTERNAL;
- return NS_NOTFOUND;
- }
- }
- if (strlcat(qbuf, "ip6.arpa", sizeof(qbuf)) >= sizeof(qbuf)) {
- h_errno = NETDB_INTERNAL;
- return NS_NOTFOUND;
- }
- break;
- default:
- abort();
- }
- buf = malloc(sizeof(*buf));
- if (buf == NULL) {
- h_errno = NETDB_INTERNAL;
- return NS_NOTFOUND;
- }
- res = __res_get_state();
- if (res == NULL) {
- free(buf);
- return NS_NOTFOUND;
- }
- n = res_nquery(res, qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf));
- if (n < 0) {
- free(buf);
- debugprintf("res_nquery failed (%d)\n", res, n);
- __res_put_state(res);
- return NS_NOTFOUND;
- }
- hp = getanswer(buf, n, qbuf, T_PTR, res);
- free(buf);
- if (hp == NULL) {
- __res_put_state(res);
- switch (h_errno) {
- case HOST_NOT_FOUND:
- return NS_NOTFOUND;
- case TRY_AGAIN:
- return NS_TRYAGAIN;
- default:
- return NS_UNAVAIL;
- }
- }
- hp->h_addrtype = af;
- hp->h_length = len;
- (void)memcpy(host_addr, uaddr, (size_t)len);
- h_addr_ptrs[0] = (char *)(void *)host_addr;
- h_addr_ptrs[1] = NULL;
- if (af == AF_INET && (res->options & RES_USE_INET6)) {
- map_v4v6_address((char *)(void *)host_addr,
- (char *)(void *)host_addr);
- hp->h_addrtype = AF_INET6;
- hp->h_length = IN6ADDRSZ;
- }
- __res_put_state(res);
- *((struct hostent **)rv) = hp;
- h_errno = NETDB_SUCCESS;
- return NS_SUCCESS;
- }
- #ifdef YP
- /*ARGSUSED*/
- struct hostent *
- _yphostent(char *line, int af)
- {
- static struct in_addr host_addrs[MAXADDRS];
- static struct in6_addr host6_addrs[MAXADDRS];
- char *p = line;
- char *cp, **q;
- char **hap;
- int addrok;
- int more;
- size_t naddrs;
- _DIAGASSERT(line != NULL);
- host.h_name = NULL;
- host.h_addr_list = h_addr_ptrs;
- host.h_addrtype = af;
- switch (af) {
- case AF_INET:
- host.h_length = INADDRSZ;
- break;
- case AF_INET6:
- host.h_length = IN6ADDRSZ;
- break;
- default:
- return NULL;
- }
- hap = h_addr_ptrs;
- q = host.h_aliases = host_aliases;
- naddrs = 0;
- nextline:
- /* check for host_addrs overflow */
- if (naddrs >= sizeof(host_addrs) / sizeof(host_addrs[0]))
- goto done;
- if (naddrs >= sizeof(host6_addrs) / sizeof(host6_addrs[0]))
- goto done;
- more = 0;
- cp = strpbrk(p, " \t");
- if (cp == NULL)
- goto done;
- *cp++ = '\0';
- /* p has should have an address */
- addrok = 0;
- switch (af) {
- case AF_INET:
- addrok = inet_aton(p, &host_addrs[naddrs]);
- break;
- case AF_INET6:
- addrok = inet_pton(af, p, &host6_addrs[naddrs]);
- break;
- }
- if (addrok != 1) {
- /* skip to the next line */
- while (cp && *cp) {
- if (*cp == '\n') {
- cp++;
- goto nextline;
- }
- cp++;
- }
- goto done;
- }
- switch (af) {
- case AF_INET:
- *hap++ = (char *)(void *)&host_addrs[naddrs++];
- break;
- case AF_INET6:
- *hap++ = (char *)(void *)&host6_addrs[naddrs++];
- break;
- }
- while (*cp == ' ' || *cp == '\t')
- cp++;
- p = cp;
- cp = strpbrk(p, " \t\n");
- if (cp != NULL) {
- if (*cp == '\n')
- more = 1;
- *cp++ = '\0';
- }
- if (!host.h_name)
- host.h_name = p;
- else if (strcmp(host.h_name, p)==0)
- ;
- else if (q < &host_aliases[MAXALIASES - 1])
- *q++ = p;
- p = cp;
- if (more)
- goto nextline;
- while (cp && *cp) {
- if (*cp == ' ' || *cp == '\t') {
- cp++;
- continue;
- }
- if (*cp == '\n') {
- cp++;
- goto nextline;
- }
- if (q < &host_aliases[MAXALIASES - 1])
- *q++ = cp;
- cp = strpbrk(cp, " \t");
- if (cp != NULL)
- *cp++ = '\0';
- }
- done:
- if (host.h_name == NULL)
- return NULL;
- *q = NULL;
- *hap = NULL;
- return &host;
- }
- /*ARGSUSED*/
- int
- _yp_gethtbyaddr(void *rv, void *cb_data, va_list ap)
- {
- struct hostent *hp = NULL;
- static char *__ypcurrent;
- int __ypcurrentlen, r;
- char name[INET6_ADDRSTRLEN]; /* XXX enough? */
- const unsigned char *uaddr;
- int af;
- const char *map;
- _DIAGASSERT(rv != NULL);
- uaddr = va_arg(ap, unsigned char *);
- /* NOSTRICT skip len */(void)va_arg(ap, int);
- af = va_arg(ap, int);
-
- if (!__ypdomain) {
- if (_yp_check(&__ypdomain) == 0)
- return NS_UNAVAIL;
- }
- /*
- * XXX unfortunately, we cannot support IPv6 extended scoped address
- * notation here. gethostbyaddr() is not scope-aware. too bad.
- */
- if (inet_ntop(af, uaddr, name, sizeof(name)) == NULL)
- return NS_UNAVAIL;
- if (__ypcurrent)
- free(__ypcurrent);
- __ypcurrent = NULL;
- switch (af) {
- case AF_INET:
- map = "hosts.byaddr";
- break;
- default:
- map = "ipnodes.byaddr";
- break;
- }
- r = yp_match(__ypdomain, map, name,
- (int)strlen(name), &__ypcurrent, &__ypcurrentlen);
- if (r == 0)
- hp = _yphostent(__ypcurrent, af);
- if (hp == NULL) {
- h_errno = HOST_NOT_FOUND;
- return NS_NOTFOUND;
- }
- *((struct hostent **)rv) = hp;
- return NS_SUCCESS;
- }
- /*ARGSUSED*/
- int
- _yp_gethtbyname(void *rv, void *cb_data, va_list ap)
- {
- struct hostent *hp = NULL;
- static char *__ypcurrent;
- int __ypcurrentlen, r;
- const char *name;
- int af;
- const char *map;
- _DIAGASSERT(rv != NULL);
- name = va_arg(ap, char *);
- /* NOSTRICT skip len */(void)va_arg(ap, int);
- af = va_arg(ap, int);
- if (!__ypdomain) {
- if (_yp_check(&__ypdomain) == 0)
- return NS_UNAVAIL;
- }
- if (__ypcurrent)
- free(__ypcurrent);
- __ypcurrent = NULL;
- switch (af) {
- case AF_INET:
- map = "hosts.byname";
- break;
- default:
- map = "ipnodes.byname";
- break;
- }
- r = yp_match(__ypdomain, map, name,
- (int)strlen(name), &__ypcurrent, &__ypcurrentlen);
- if (r == 0)
- hp = _yphostent(__ypcurrent, af);
- if (hp == NULL) {
- h_errno = HOST_NOT_FOUND;
- return NS_NOTFOUND;
- }
- *((struct hostent **)rv) = hp;
- return NS_SUCCESS;
- }
- #endif