/* $OpenBSD: gethostnamadr.c,v 1.71 2007/05/16 04:14:23 ray Exp $ */ /*- * 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 #include #include #include #include #include #include #include #include #include #include #include #include #ifdef YP #include #include #include #include "ypinternal.h" #endif #include "thread_private.h" #define MULTI_PTRS_ARE_ALIASES 1 /* XXX - experimental */ #define MAXALIASES 35 #define MAXADDRS 35 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[BUFSIZ+1]; static union { struct in_addr _host_in_addr; u_char _host_addr[16]; /* IPv4 or IPv6 */ } _host_addr_u; #define host_addr _host_addr_u._host_addr static FILE *hostf = NULL; static int stayopen = 0; static void map_v4v6_address(const char *src, char *dst); static void map_v4v6_hostent(struct hostent *hp, char **bp, char *); #ifdef RESOLVSORT static void addrsort(char **, int); #endif int _hokchar(const char *); static const char AskedForGot[] = "gethostby*.getanswer: asked for \"%s\", got \"%s\""; #define MAXPACKET (64*1024) typedef union { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; typedef union { int32_t al; char ac; } align; static struct hostent *getanswer(const querybuf *, int, const char *, int); extern int h_errno; int _hokchar(const char *p) { char c; /* * Many people do not obey RFC 822 and 1035. The valid * characters are a-z, A-Z, 0-9, '-' and . But the others * tested for below can happen, and we must be more permissive * than the resolver until those idiots clean up their act. * We let '/' through, but not '..' */ while ((c = *p++)) { if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9')) continue; if (strchr("-_/", c)) continue; if (c == '.' && *p != '.') continue; return 0; } return 1; } static struct hostent * getanswer(const querybuf *answer, int anslen, const char *qname, int qtype) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); const HEADER *hp; const u_char *cp, *eom; char tbuf[MAXDNAME]; char *bp, **ap, **hap, *ep; int type, class, ancount, qdcount, n; int haveanswer, had_error, toobig = 0; const char *tname; int (*name_ok)(const char *); tname = qname; host.h_name = NULL; eom = answer->buf + anslen; switch (qtype) { case T_A: case T_AAAA: #ifdef USE_RESOLV_NAME_OK name_ok = res_hnok; break; #endif case T_PTR: #ifdef USE_RESOLV_NAME_OK name_ok = res_dnok; #else name_ok = _hokchar; #endif break; default: return (NULL); } /* * find first satisfactory answer */ hp = &answer->hdr; ancount = ntohs(hp->ancount); qdcount = ntohs(hp->qdcount); bp = hostbuf; ep = hostbuf + sizeof hostbuf; cp = answer->buf + 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); } cp += 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). */ host.h_name = bp; bp += strlen(bp) + 1; /* for the \0 */ /* 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) { size_t len; n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { had_error++; continue; } cp += n; /* name */ if (cp >= eom) break; type = _getshort(cp); cp += INT16SZ; /* type */ if (cp >= eom) break; class = _getshort(cp); cp += INT16SZ + INT32SZ; /* class, TTL */ if (cp >= eom) break; n = _getshort(cp); cp += INT16SZ; /* len */ if (cp >= eom) break; if (type == T_SIG) { /* XXX - ignore signatures as we don't use them yet */ cp += n; continue; } 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; /* Store alias. */ *ap++ = bp; bp += strlen(bp) + 1; /* for the \0 */ /* Get canonical name. */ len = strlen(tbuf) + 1; /* for the \0 */ if (len > ep - bp) { had_error++; continue; } strlcpy(bp, tbuf, ep - bp); host.h_name = bp; bp += len; continue; } if (qtype == T_PTR && type == T_CNAME) { n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); #ifdef USE_RESOLV_NAME_OK if ((n < 0) || !res_hnok(tbuf)) { #else if ((n < 0) || !_hokchar(tbuf)) { #endif had_error++; continue; } cp += n; /* Get canonical name. */ len = strlen(tbuf) + 1; /* for the \0 */ if (len > ep - bp) { had_error++; continue; } strlcpy(bp, tbuf, ep - bp); tname = bp; bp += len; continue; } if (type != qtype) { 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); #ifdef USE_RESOLV_NAME_OK if ((n < 0) || !res_hnok(bp)) { #else if ((n < 0) || !_hokchar(bp)) { #endif had_error++; break; } #if MULTI_PTRS_ARE_ALIASES cp += n; 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 */ bp += n; } break; #else host.h_name = bp; if (_resp->options & RES_USE_INET6) { n = strlen(bp) + 1; /* for the \0 */ 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) { host.h_name = bp; bp += strlen(bp) + 1; /* for the \0 */ } bp += sizeof(align) - ((u_long)bp % sizeof(align)); if (bp + n >= &hostbuf[sizeof hostbuf]) { #ifdef DEBUG if (_resp->options & RES_DEBUG) printf("size (%d) too big\n", n); #endif had_error++; continue; } if (hap >= &h_addr_ptrs[MAXADDRS-1]) { if (!toobig++) #ifdef DEBUG if (_resp->options & RES_DEBUG) printf("Too many addresses (%d)\n", MAXADDRS); #endif cp += n; continue; } bcopy(cp, *hap++ = bp, n); bp += n; cp += n; break; } if (!had_error) haveanswer++; } if (haveanswer) { *ap = NULL; *hap = NULL; # if defined(RESOLVSORT) /* * 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 (_resp->nsort && haveanswer > 1 && qtype == T_A) addrsort(h_addr_ptrs, haveanswer); # endif /*RESOLVSORT*/ if (!host.h_name) { size_t len; len = strlen(qname) + 1; if (len > ep - bp) /* for the \0 */ goto try_again; strlcpy(bp, qname, ep - bp); host.h_name = bp; bp += len; } if (_resp->options & RES_USE_INET6) map_v4v6_hostent(&host, &bp, ep); h_errno = NETDB_SUCCESS; return (&host); } try_again: h_errno = TRY_AGAIN; return (NULL); } #ifdef notyet /* * XXX This is an extremely bogus implementation. * * FreeBSD has this interface: * int gethostbyaddr_r(const char *addr, int len, int type, * struct hostent *result, struct hostent_data *buffer) */ struct hostent * gethostbyname_r(const char *name, struct hostent *hp, char *buf, int buflen, int *errorp) { struct hostent *res; res = gethostbyname(name); *errorp = h_errno; if (res == NULL) return NULL; memcpy(hp, res, sizeof *hp); /* XXX not sufficient */ return hp; } /* * XXX This is an extremely bogus implementation. */ struct hostent * gethostbyaddr_r(const char *addr, int len, int af, struct hostent *he, char *buf, int buflen, int *errorp) { struct hostent * res; res = gethostbyaddr(addr, len, af); *errorp = h_errno; if (res == NULL) return NULL; memcpy(he, res, sizeof *he); /* XXX not sufficient */ return he; } /* XXX RFC2133 expects a gethostbyname2_r() -- unimplemented */ #endif struct hostent * gethostbyname(const char *name) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); struct hostent *hp; extern struct hostent *_gethtbyname2(const char *, int); if (_res_init(0) == -1) hp = _gethtbyname2(name, AF_INET); else if (_resp->options & RES_USE_INET6) { hp = gethostbyname2(name, AF_INET6); if (hp == NULL) hp = gethostbyname2(name, AF_INET); } else hp = gethostbyname2(name, AF_INET); return hp; } struct hostent * gethostbyname2(const char *name, int af) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); querybuf *buf; const char *cp; char *bp, *ep; int n, size, type, i; struct hostent *hp; char lookups[MAXDNSLUS]; extern struct hostent *_gethtbyname2(const char *, int); #ifdef YP extern struct hostent *_yp_gethtbyname(const char *); #endif if (_res_init(0) == -1) return (_gethtbyname2(name, af)); switch (af) { case AF_INET: size = INADDRSZ; type = T_A; break; case AF_INET6: size = IN6ADDRSZ; type = T_AAAA; 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_query() 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(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, host_addr) <= 0) { h_errno = HOST_NOT_FOUND; return (NULL); } strlcpy(hostbuf, name, MAXHOSTNAMELEN); bp = hostbuf + MAXHOSTNAMELEN; ep = hostbuf + sizeof(hostbuf); host.h_name = hostbuf; host.h_aliases = host_aliases; host_aliases[0] = NULL; h_addr_ptrs[0] = (char *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; if (_resp->options & RES_USE_INET6) map_v4v6_hostent(&host, &bp, ep); h_errno = NETDB_SUCCESS; return (&host); } if (!isdigit(*cp) && *cp != '.') break; } if ((isxdigit(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, host_addr) <= 0) { h_errno = HOST_NOT_FOUND; return (NULL); } strlcpy(hostbuf, name, MAXHOSTNAMELEN); bp = hostbuf + MAXHOSTNAMELEN; ep = hostbuf + sizeof(hostbuf); host.h_name = hostbuf; host.h_aliases = host_aliases; host_aliases[0] = NULL; h_addr_ptrs[0] = (char *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; h_errno = NETDB_SUCCESS; return (&host); } if (!isxdigit(*cp) && *cp != ':' && *cp != '.') break; } bcopy(_resp->lookups, lookups, sizeof lookups); if (lookups[0] == '\0') strlcpy(lookups, "bf", sizeof lookups); hp = (struct hostent *)NULL; for (i = 0; i < MAXDNSLUS && hp == NULL && lookups[i]; i++) { switch (lookups[i]) { #ifdef YP case 'y': /* YP only supports AF_INET. */ if (af == AF_INET) hp = _yp_gethtbyname(name); break; #endif case 'b': buf = malloc(sizeof(*buf)); if (buf == NULL) break; if ((n = res_search(name, C_IN, type, buf->buf, sizeof(buf->buf))) < 0) { free(buf); #ifdef DEBUG if (_resp->options & RES_DEBUG) printf("res_search failed\n"); #endif break; } hp = getanswer(buf, n, name, type); free(buf); break; case 'f': hp = _gethtbyname2(name, af); break; } } /* XXX h_errno not correct in all cases... */ return (hp); } struct hostent * gethostbyaddr(const void *addr, socklen_t len, int af) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); const u_char *uaddr = (const u_char *)addr; int n, size, i; querybuf *buf; struct hostent *hp; char qbuf[MAXDNAME+1], *qp, *ep; char lookups[MAXDNSLUS]; struct hostent *res; extern struct hostent *_gethtbyaddr(const void *, socklen_t, int); #ifdef YP extern struct hostent *_yp_gethtbyaddr(const void *); #endif if (_res_init(0) == -1) { res = _gethtbyaddr(addr, len, af); return (res); } if (af == AF_INET6 && len == IN6ADDRSZ && (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)uaddr) || IN6_IS_ADDR_SITELOCAL((struct in6_addr *)uaddr))) { h_errno = HOST_NOT_FOUND; return (NULL); } if (af == AF_INET6 && len == IN6ADDRSZ && (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)uaddr) || IN6_IS_ADDR_V4COMPAT((struct in6_addr *)uaddr))) { /* Unmap. */ 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); } ep = qbuf + sizeof(qbuf); 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; for (n = IN6ADDRSZ - 1; n >= 0; n--) { i = snprintf(qp, ep - qp, "%x.%x.", uaddr[n] & 0xf, (uaddr[n] >> 4) & 0xf); if (i <= 0 || i >= ep - qp) { errno = EINVAL; h_errno = NETDB_INTERNAL; return (NULL); } qp += i; } strlcpy(qp, "ip6.arpa", ep - qp); break; } bcopy(_resp->lookups, lookups, sizeof lookups); if (lookups[0] == '\0') strlcpy(lookups, "bf", sizeof lookups); hp = (struct hostent *)NULL; for (i = 0; i < MAXDNSLUS && hp == NULL && lookups[i]; i++) { switch (lookups[i]) { #ifdef YP case 'y': /* YP only supports AF_INET. */ if (af == AF_INET) hp = _yp_gethtbyaddr(uaddr); break; #endif case 'b': buf = malloc(sizeof(*buf)); if (!buf) break; n = res_query(qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf)); if (n < 0) { free(buf); #ifdef DEBUG if (_resp->options & RES_DEBUG) printf("res_query failed\n"); #endif break; } if (!(hp = getanswer(buf, n, qbuf, T_PTR))) { free(buf); break; } free(buf); hp->h_addrtype = af; hp->h_length = len; bcopy(uaddr, host_addr, len); h_addr_ptrs[0] = (char *)host_addr; h_addr_ptrs[1] = NULL; if (af == AF_INET && (_resp->options & RES_USE_INET6)) { map_v4v6_address((char*)host_addr, (char*)host_addr); hp->h_addrtype = AF_INET6; hp->h_length = IN6ADDRSZ; } h_errno = NETDB_SUCCESS; break; case 'f': hp = _gethtbyaddr(uaddr, len, af); break; } } /* XXX h_errno not correct in all cases... */ return (hp); } void _sethtent(int f) { if (hostf == NULL) hostf = fopen(_PATH_HOSTS, "r" ); else rewind(hostf); stayopen = f; } void _endhtent(void) { if (hostf && !stayopen) { (void) fclose(hostf); hostf = NULL; } } static struct hostent * _gethtent(void) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); char *p, *cp, **q; int af; size_t len; if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) { h_errno = NETDB_INTERNAL; return (NULL); } again: if ((p = fgetln(hostf, &len)) == NULL) { h_errno = HOST_NOT_FOUND; return (NULL); } if (p[len-1] == '\n') len--; if (len >= sizeof(hostbuf) || len == 0) goto again; p = memcpy(hostbuf, p, len); hostbuf[len] = '\0'; if (*p == '#') goto again; if ((cp = strchr(p, '#'))) *cp = '\0'; if (!(cp = strpbrk(p, " \t"))) goto again; *cp++ = '\0'; if (inet_pton(AF_INET6, p, host_addr) > 0) { af = AF_INET6; len = IN6ADDRSZ; } else if (inet_pton(AF_INET, p, host_addr) > 0) { if (_resp->options & RES_USE_INET6) { map_v4v6_address((char*)host_addr, (char*)host_addr); af = AF_INET6; len = IN6ADDRSZ; } else { af = AF_INET; len = INADDRSZ; } } else { goto again; } /* if this is not something we're looking for, skip it. */ if (host.h_addrtype != AF_UNSPEC && host.h_addrtype != af) goto again; if (host.h_length != 0 && host.h_length != len) goto again; h_addr_ptrs[0] = (char *)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"))) *cp++ = '\0'; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (q < &host_aliases[MAXALIASES - 1]) *q++ = cp; if ((cp = strpbrk(cp, " \t"))) *cp++ = '\0'; } *q = NULL; if (_resp->options & RES_USE_INET6) { char *bp = hostbuf; char *ep = hostbuf + sizeof hostbuf; map_v4v6_hostent(&host, &bp, ep); } h_errno = NETDB_SUCCESS; return (&host); } struct hostent * _gethtbyname2(const char *name, int af) { struct hostent *p; char **cp; _sethtent(0); while ((p = _gethtent())) { if (p->h_addrtype != af) continue; if (strcasecmp(p->h_name, name) == 0) break; for (cp = p->h_aliases; *cp != 0; cp++) if (strcasecmp(*cp, name) == 0) goto found; } found: _endhtent(); return (p); } struct hostent * _gethtbyaddr(const void *addr, socklen_t len, int af) { struct hostent *p; host.h_length = len; host.h_addrtype = af; _sethtent(0); while ((p = _gethtent())) if (p->h_addrtype == af && p->h_length == len && !bcmp(p->h_addr, addr, len)) break; _endhtent(); return (p); } #ifdef YP struct hostent * _yphostent(char *line) { static struct in_addr host_addrs[MAXADDRS]; char *p = line; char *cp, **q; char **hap; struct in_addr *buf; int more; host.h_name = NULL; host.h_addr_list = h_addr_ptrs; host.h_length = INADDRSZ; host.h_addrtype = AF_INET; hap = h_addr_ptrs; buf = host_addrs; q = host.h_aliases = host_aliases; nextline: /* check for host_addrs overflow */ if (buf >= &host_addrs[sizeof(host_addrs) / sizeof(host_addrs[0])]) goto done; more = 0; cp = strpbrk(p, " \t"); if (cp == NULL) goto done; *cp++ = '\0'; *hap++ = (char *)buf; (void) inet_aton(p, buf++); 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); } struct hostent * _yp_gethtbyaddr(const void *addr) { struct hostent *hp = NULL; const u_char *uaddr = (const u_char *)addr; static char *__ypcurrent; int __ypcurrentlen, r; char name[sizeof("xxx.xxx.xxx.xxx")]; if (!__ypdomain) { if (_yp_check(&__ypdomain) == 0) return (hp); } snprintf(name, sizeof name, "%u.%u.%u.%u", (uaddr[0] & 0xff), (uaddr[1] & 0xff), (uaddr[2] & 0xff), (uaddr[3] & 0xff)); if (__ypcurrent) free(__ypcurrent); __ypcurrent = NULL; r = yp_match(__ypdomain, "hosts.byaddr", name, strlen(name), &__ypcurrent, &__ypcurrentlen); if (r==0) hp = _yphostent(__ypcurrent); if (hp==NULL) h_errno = HOST_NOT_FOUND; return (hp); } struct hostent * _yp_gethtbyname(const char *name) { struct hostent *hp = (struct hostent *)NULL; static char *__ypcurrent; int __ypcurrentlen, r; if (strlen(name) >= MAXHOSTNAMELEN) return (NULL); if (!__ypdomain) { if (_yp_check(&__ypdomain) == 0) return (hp); } if (__ypcurrent) free(__ypcurrent); __ypcurrent = NULL; r = yp_match(__ypdomain, "hosts.byname", name, strlen(name), &__ypcurrent, &__ypcurrentlen); if (r == 0) hp = _yphostent(__ypcurrent); if (hp == NULL) h_errno = HOST_NOT_FOUND; return (hp); } #endif static void map_v4v6_address(const char *src, char *dst) { u_char *p = (u_char *)dst; char tmp[INADDRSZ]; int i; /* Stash a temporary copy so our caller can update in place. */ bcopy(src, tmp, 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. */ bcopy(tmp, (void*)p, INADDRSZ); } static void map_v4v6_hostent(struct hostent *hp, char **bpp, char *ep) { char **ap; 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) - ((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; } } struct hostent * gethostent(void) { host.h_addrtype = AF_UNSPEC; host.h_length = 0; return (_gethtent()); } #ifdef RESOLVSORT static void addrsort(char **ap, int num) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); int i, j; char **p; short aval[MAXADDRS]; int needsort = 0; p = ap; for (i = 0; i < num; i++, p++) { for (j = 0 ; (unsigned)j < _resp->nsort; j++) if (_resp->sort_list[j].addr.s_addr == (((struct in_addr *)(*p))->s_addr & _resp->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++; } } #endif